Campfire Starters - stuff toilet paper rolls with dryer lint. You can even roll and wrap in newspaper. Toilet paper rolls and dryer lint are an inexpensive DIY project - in fact free and you are recycling!
DIY Cooler - You take a smaller pot and put it inside a larger pot. Fill the space in between them with wet sand, and cover the top with a wet cloth. As the water evaporates from the sand, it pulls the heat out with it, cooling the inner pot.
2 Liter Bottles of Light provide as much light as a 50 watt light globe. The slums of the Philippines are getting an extreme home makeover in the form of two liter bottles in their ceilings. The bott (Bottle Lights Ceiling)