To help you save money, save time and lose stress.
Keep a small Tupperware container filled with your interior paint color. That way when you need to do periodic touch ups, you can just pull it out, stir with a brush, and fix them. Breaking out the 5-gallon bucket is usually a production.
Do not mix bleach and ammonia.
Coffee grounds are magic. They are a great fertilizer, and a systemic pesticide that is non-toxic to humans and pets. Let them cool and sprinkle around your plants and windows. If you need to do a big fertilizing job in the spring, call your local Starbucks and offer to take their grounds away for a day or two.
If the air quality in your house sucks, you may need to run the AC less and open the windows more. Most homes with central AC have a "split system." This cools or heats the air, but does not bring in fresh air. It just recirculates the air in your house at a different temperature.
White vinegar is a good substitute for many household cleaners (so called 'General Purpose Cleaners'). Buy a cheap spray bottle and fill it with vinegar undiluted. It is perfect for quick clean ups around the kitchen and bathroom as it is both a disinfectant AND completely volatile (it will smell for a while but evaporate to leave no residues). It is also good at cleaning glass and hundreds of other things.
To keep drains unblocked in the long run: Buy some sodium hydroxide, lye, (in bulk - say 2 or 3 kg size - it's cheaper) at hardware stores. Use a tablespoon full each week in your drains/sinks around the house. Rinse with cold water. This should prevent all future blockages unless you are putting some crazy shit down your drains. It will also dissolve hair in your shower drain (however for a quick fix, the sulfuric acid based drain 'unblockers' are even better at this).
To remove smells from drains/sinks, first put hot water down the drain. Then, add concentrated ('premium') chlorine bleach carefully so that it pours into all sides of the pipe. Cover/plug and then leave for 1 hour. Rinse with hot water. Repeat until the problem goes away (it will!).
Hydrogen peroxide (sold often at pharmacies, but becoming harder to find?) is another multi-use substance. It has medical uses (cleaning cuts/scrapes), cleaning uses (removing strong stains), and even plant-growing uses. Learn its many uses and keep a small bottle in the fridge (it will last longer) for the right occasion. 5 to 10% concentration is usually sold. It eventually breaks down into water and oxygen gas.
The cheapest dishwashing detergent is as good as the most expensive. Antibacterial varieties seem trivial since most bacteria can't withstand being hit with surfactants, which is essentially all that any detergent is.
Know what you are buying: Learning about the substances in your cleaners can let you compare brands and prices and save you money in the long run.
Buy a Kill-o-watt or similar electricity metering device that can measure power consumption of appliances, they're about $30 or less.
A $5 portable AM radio can easily find devices causing interference with your wifi in your home. For example, I had a faulty or poorly designed AC power pack that was causing so much EMI that it was disconnecting my ADSL modem some 2 meters away and causing wifi dropouts. Easily found with the AM radio and resolved by moving that equipment to another room.
Insulation is a really good investment for your short term comfort but more importantly your long term finances.
Heaters which directly heat air are relatively expensive to run and often not much more effective than if you just put on more clothes. If you are just heating a small area, for example your couch or study desk area, then radiant heaters with quartz halogen bulbs are a far cheaper and more effective option.
If you want to heat the air in winter, use a reverse cycle air conditioner. Because air conditioners are heat pumps, their overall efficiency is far greater than conventional heaters which directly heat the air using hot elements (oil heaters, fan heaters, etc).
For cooling, steer away from portable air conditioners. They are very inefficient by design unless they have BOTH a pipe for venting hot air and a pipe for bringing inside cooler air. Basically, the single vent designs are very inefficient because they create a negative pressure inside the home causing hot outside air to flow into the house nullifying the cooling effect of the machine.
Depending on your climate, solar hot water is a really good option and pays for itself quite quickly. Solar photovoltaics is good in the very long run (10 years+) if you can afford the initial outlay.
Saving energy by turning off standby devices is bullshit for most people most of the time. You are far more likely to save money from changing the way you heat/cool your rooms, the way you heat your hot water, and by changing the way and how often you use your larger appliances - and if you are like me - your computers.
If your microwave is really dirty, put a damp cloth in there for about 30-45 seconds, let it sit (to cool down) then use it to wipe away all the crap. The steam releases all the stuck on food, like the dried up stuff you would end up scraping off.
If you drop something tiny on the floor you can find it by placing flashlight (the more powerful the better) on the floor and pointing it parallel to it. Even the smallest object on it will cast a huge shadow on the floor.
Take 5-10 minutes at the end of each day to clean up whatever mess you have made during the day. Never again will you have to spend hours cleaning.
Wash just after you finish cooking, because you are really hungry for the food you just cooked you blast through those pots and pans like a madman.
If you own a car or a property and you don't have a high pressure cleaner then you are doing it wrong. Even a cheap (<$150) pressure cleaner will make your life so much easier and your car so much shinier. (Be careful with your cars paint and spraying too close. My pressure cleaner has a car cleaning attachment nozzle thing.)
If you haven't used it in 2 years, throw it out. If you haven't worn it in the last 4 seasons, throw it out or donate it to charity. To arrange your clothes by how they are used in your wardrobe, always put things into the wardrobe hanging them on the same side (left or right). The clothes that accumulate on the opposite side after 1 year are the things you dont wear and can be thrown out or donated to charity.
After putting a sheet set through the laundry, store the sheets (and one pillowcase) inside the other pillowcase. You'll never search for the matching sheet/pillowcase again.
Toothpaste polishes silver beautifully.
When indentations are left in carpet after moving furniture around, put an ice cube in the spot to melt overnight and the carpet will be fluffed back up in the morning!
Lemon juice is a wonderful cleaning agent no one thinks about.
No space? Small unit? Think vertically! I spent ~$2000 at Ikea and have about 4x the volume of 'stuff' which some of my friends have, yet my stuff occupies a quarter of the overall floorspace.
If you have problems with a smelly fridge: First and foremost clean out the bad stuff. Then put a few slices of lemon on a plate and it'll smell good in no time!
Microfiber cloths are AWESOME for cleaning. They can clean anything with just a little water. Mirrors, glass, appliances...heck they can even take off the soap scum on shower walls (although that takes a bit of elbow grease). Using damp microfiber cloths is a great way to cut down on the paper towel and chemical use when you clean.
Cheap shampoo is great on the soap scum.
If you like using the dishwasher, make sure you buy dishwasher-safe pots.
Used dryer sheets for dusting. Almost as effective as those expensive Swiffer things.
Fill a Pint or Quart sized container (chinese soup container basically) half full with water. Freeze the container. Put a penny on top of the ice. If you go out of town when you come home check the container; if it is still frozen with the penny on top you didn't lose power. If the ice has reformed and the penny is at the bottom or middle, your lost power and your freezer became warm enough for food to defrost and is now no good and should be thrown out.
WD40 dissolves glues. So if you buy a fridge or something that has those irritating stickers on them "Now with therma thumper cool!", spray WD40 where you ripped the sticker off and wipe. Glue gone.
Toothpaste rubbed gently on wooden furniture removes heat marks.
Make it a point to do one thing extra around the house every day. It does not have to be big, just something that you would not normally do when you go about your everyday life. Over time, this makes a big difference in the amount of order/cleanliness in your life.
If you use up all the paint in the can throw the can away and throw the lid in a Ziploc bag, most places put a sticker on top with all the info on it to remake the paint even if it's custom or the dried pain on the lid can be used for a match.
The best way to peel hard boiled eggs is under running water. Makes them peel great every time without mutilating the eggs.
Always clean from the top down - i.e., start with the top of your cabinets, then the countertops, then the floor. This way the dirt and dust works its way down to the last thing you clean.
Put replacement trash bags in the bottom of the trash can for easy access.
Instead of buying those expensive gel ice packs, take a large zip lock freezer bag, fill it to about 1/3 full with 3 parts water to one part rubbing alcohol, then seal it, being careful to work the air out of it. Then put that bag inside another bag. The bag will freeze to a super cold slush that never solidifies.
When you're done with a sponge, squeeze it out and place it scrubby side down. This will keep it from smelling and your hands will only smell like soap after handling it.
Tea bags will deodorize and clean an ashtray, cup, bowl, that has been used as an ashtray, whether it should have been or not. Just wet with warm water or take a used one and work like a sponge.
Have a tough stain on your countertop? Use powdered dishwashing soap. Wet the stain, sprinkle on some soap and rub with a sponge.
To get the old musty smell out of towels wash them with hot water and a cup of vinegar. Then immediately rewash them normally with regular laundry detergent.
When you are done with a sponge, ring it out and put it in the microwave for one minute. It will disinfect it and get it almost dry. This will keep it sanitary and from smelling gross.
To clean your coffee pot, Run a brew with only vinegar, and then run it with only water. Lastly, use a slice of bread to wipe out the entire thing.
If you break a glass, use a piece of bread to sponge the area where the pieces shattered. It picks up the smaller slivers of glass.
Water sometimes doesn't boil in microwave ovens if it is clean enough. Add impurities(salt, sugar, anything really) to make it boil instantly if it's already been in, or beforehand if boiling is necessary.
Grains of rice in the salt-jar = no lumps!
Clean your sink every day. If your sink is clean you will have no psychological excuse to not clean the rest of your kitchen.
When making toast and your butter is hard from refrigeration, use a cheese grater on the butter over the toast. No more holes in the toast from scraping hard butter on it.
Don't buy anything unless you have a place for it. Keep your home free of clutter.
Buy what you need. Use what you buy.
If you're already clutterfucked, for every new item you bring home, throw out two old ones.
Go through your house every once in a while for things that you don't need anymore. Sell it or give it away.
Turn all your hangers in your closet inside-out, the opposite way you would normally hang them. When you use the clothes on the hangers, hang them back up normally. At the end of a year, donate to Goodwill all the stuff on hangers that hasn't been turned right-side in by using it.
On some textured surfaces, cleaning grime out of the little cracks can be difficult. Mix some baking soda with water so that it becomes a paste, then spread a thin layer of it over all the surface you're trying to clean. Next, wipe over it with a sponge filled with vinegar. The bubbling reaction helps to remove a lot of the built-up gunk.
If you have fruit flies in your kitchen, pour some vinegar in a small dish and add a couple of drops of liquid dish soap - Boom! they drown.
To help prevent fruit flies in the first place, rinse your bananas as soon as you bring them home from the store.
To help you decide what clothes to declutter from your closet, turn all your hangers backwards, so the open part of the hook faces out. Then, as you put your clothes away, hang them the normal way. After x number of months (I usually do 6 month increments), remove the clothes you haven't worn in that time period and donate them.