Pulserifle from the Alien movie. Should count as a post apocalypse weapon.
Rendertime: 2min 19sec.
EDIT
Here are an updated version with some of the textures, couldn't find all of them.
Rendertime: 50sec.
Got inspired when I saw fife's http://zero-press.fifengine.de/pr_001_april_2006/Zero-stimpack.png so I thought I would make one to. Just a simple clay render and a little poly speed modeling.
UPDATE 06.05.06
Rendertime: 2min.