I cant run Fallout 3 on any of my PC's, but I'm curious, is there anything like the GECK for Fallout 1 and 2?

There is an editor for Fallout 2, but it's very hard to use compared to Fallout 3's GECK.

There are save game editors as well, if all you want to do is tweak stats. I've also seen modified saved games. For example, one had Klamath filled with all kinds of items.