The Blue Lagoon, Iceland, is a geothermal spa. The outdoor bath remains 100-110°F year round. The natural ingredients of the warm water: mineral salts, white silica and blue green algae. These ingredients clean exfoliate, nourish & soften the skin while relaxing the body.
Some of these suggestions are things I would like to do, but others seem unnecessary. Like, how cool is it that you can mix Mtn Dew with baking soda and peroxide and it will glow! Amazing! Or you could just, you know, use a lantern and stuff. The post also has a couple more good, kind of labor intensive, ideas for firestarters.