Ever hear of these prefab homes: the Lanta House? Doomak House? Simphan House? Without knowing better, you might guess that these prefabs were designed by Michelle Kaufmann Designs or Marmol Radziner + Associates. Well, they're not. In fact, the above prefabs don't even exist in the real world. They were created for use in the on-line game Second Life. That's right, a prefab, created on-line for use in a computer game, with a small environmental footprint but sold for cash. Confused?