When I see sites like these it really makes me want to play with my legos again (which are on the other end of the state at my mom's place, somewhere under a pile of stuff...):

http://onyx.malagraphixia.com/onyx.htm

These are especially cool:

http://beretta9mm.malagraphixia.com/

http://mp5.malagraphixia.com/Images/H&K_MP5_1 … en_Extended.gif
[sorry the image doesn't appear inline - the message board is being stupid so I made it a URL instead]
http://mp5.malagraphixia.com/

I never even dreamed of making stuff that cool when I was a kid. Well, I did always dream of making transformable robots from legos - the closest I got was making Veritech/F-14 style folding wings.

EDIT: Dug up this pic I made in the fun Lego CAD program that's floating around. Someone sent it to me on IRC a couple years ago and I spent a day or two making space lego stuff that I never had enough pieces to make for real as a kid.