Ideas within topic machines,others: (click suns to rate or comment on ideas)

1 3D printer that consumes supermarket plastic bags E-mail
2 Use an internet homepage rotating tool like Whatpage. Link to several free click-to-donate websites, and each time you open up an internet browser a different click-to-donate website will appear.
3 Use windmills for intermittent power in poor, remote areas, as farms in the US plains formerly used to pump water. Use for water pumping and purification, or making ice for underground ice house. (development,electricity) E-mail
4 Apply a traser or glow-in-dark sticker to flash lights. When the power fails, you can spot and head for the flash light in the dark. E-mail
5 How many times have you gone into the basement with your hands full, fumbling for the light switch? Rig power outlet or light with a passive infrared (pir) sensor to turn on the light when it detects a person nearby, for security or convenience. E-mail
6 A digital camera which can be remotely activated by or attached to a passive infrared (pir) sensor for security. A similar example. E-mail
7 So that blind or immobile people can respond to people at their door, a hand-held intercom (like a cell phone) linked to a fixed intercom at the door. E-mail
8 In the multi-purpose exercise machines, add thin rubber lining to the adjustable weight plates. That stops annoying noise when they fall suddenly because of lack of control/practice with this equipment. E-mail
9 A lawn mower that has a bottle that you can fill with fertilizer, pesticide, etc. While you mow the lawn, the fertilizer can be spread so that you can feed and mow at the same time! E-mail
10 Computerised indoor swimming holes big enough for an adult and using elastic bands tied to ankles or waist to allow a person to swim. Saves space and costs. Computer to track duration and speed. Similar example E-mail
11 To prevent medical problems from inhaling dangerous fumes (soldering, welding, melting plastic), a simple "fume-sucker" can be constructed using an old vacuum hose with a fan attached to one end. The hose can lead outside. E-mail
12 In places where computers are left on for much of the day (internet cafes, libraries, offices), these computers could be working on distributed computing projects in the background. E-mail
13 Liquid nitrogen airplane. Instead of kerosene, fill tanks with liquid nitrogen, which vaporizes through nozzles to propel plane. Safer since no fire danger; lighter since no jet engines; no air pollution; no noise pollution. Or use compressed air. E-mail
14 Catch gray water (from washing dishes) and use for outdoor plants, vehicles. (I've seen plans for simple filtering through sand in an old barrel).
15 To save space and energy, use a tankless water heater. (Example.) They last 30+ years and are safer. They are common in crowded places such as Hong Kong. E-mail
16 Press the Mute button on your TV remote during advertisements to avoid being subliminally manipulated into buying the products/services on offer. Even though you don't want the product, the advert will have a small cumulative effect on you. (commercials) E-mail
17 A cordless telephone with a backup battery in case your electricity goes out. Also have small mic and speaker built into base unit to permit calls to be received, even when power is cut to house. Add emergency numbers as one touch buttons. E-mail
18 Save precious minutes in the shower by hooking up an extra valve to your shower head which can allow an external canister containing shampoo, conditioner, or body wash to be manually turned on or off. E-mail
19 Make an electric trumpet that is powered, like an organ, by an air pump instead of blowing air through your lips. E-mail
20 Silent vibrating watch alarms, so that if you are in a movie theater, church, etc. you can choose if it makes noise or simply vibrates like a cell phone, even lighting up to display time. E-mail
21 To take pictures of myself, it would be nice to have a camera where you can see in front of the camera whether you have your face and other parts you want framed in the photograph. E-mail
22 Measure the water pressure before and after the discharge valve in water pumping systems to analyse the energy conservation opportunity in water pumping systems. E-mail
23 Don't hurry-scurry driving. Check how much time you save in one rush--maybe 1-2 minutes. It's worth not to save that time with a good chance of an accident of any kind. Just remember to set out early by that time of 1-2 minutes and save yourself. E-mail
24 Wireless headphones (for CD/cassette players). E-mail
25 Keep batteries in the refrigerator; they last longer. E-mail
26 Build a sailplane powered by man. (airplane,bicycle,flying,hobby,glider) E-mail
27 Use a stapler made with a staple remover attached. E-mail
28 Make and place a round nail file--about one inch deep--under the metal part of a pencil. Held on by Velcro or tight enough to push up to its place, and stay there. To be used again and again. E-mail
29 A pen that's also a flashlight. E-mail
30 To reduce fumes that we breathe from mosquito repellant cake fumes and to kill instead of just repel mosquitoes, crumble and burn the cakes in a bowl in a closed room, then let the fumes out through screened windows before you stay in the room. E-mail
31 Airplane with air pump inside and hole in back. Pressing a button pulls a stick that turns on the pump, inflating a balloon that exhausts through a hole to propel the plane. E-mail
32 Save money by cancelling your home phone and just using your cell phone. (budget,telephone) E-mail
33 After shaving, hang the brush with bristles facing down. The brush dries quicker and lasts longer. E-mail
34 Supermarket shopping trollies can be joined together with lengths of rope to make a 'train', for use in the store.