If you like to be a prepper, this article may interest you.

 35 Survival Items You Can Make At Home

I have made a rocket stove out of bricks. And I made a pot of coffee with it. Didn't take a lot of wood either. Frankly it was rather surprising how easy it was to make. And the coffee wasn't too bad either. Sure beat the hell out of starbucks.

I have also made a homemade water filter, but not like any of the ones in the article. I used carbon filters I bought at Lowes. 

Charcoal will filter out a heck of a lot of stuff, but not the really nasty stuff like bacteria and virus. Etc.