There's this fellow on Youtube he's a DM and he crafts a lot of homemade stuff for his games, and I gotta tell ya, he's pretty awesome! He's got all these cool videos on how to make terrain, furniture, monsters, you name. Often he uses REALLY cheap material, in fact, you'd be amazed what he can did with some glue, paint and wet toilet paper (no, I'm not kidding on the last one.)
Anyway, if you play D&D (casts a surreptitious glance at Dark Alex) you should check him out at.
http://www.youtube.com/user/theDMsCraftSome random video samples:
Crafting Tiles
Crafting Cave Fungus
Anyway, that's just TWO of like over six hundred videos he's got.