Check out the project to create an open source self replicating 3d printer. I’m not kidding:
I don’t have the skills to build it myself, at least not without a lot more work then I want. Looking at the site, it seems for 400$ or so (look at the site for actual numbers) you can build a rapid prototyper which also happens to be self replicating, as long as you don’t include all the metal and silicon bits. It can still do a lot – for instance make a cup in which to celebrate the newly minted machine!
(on a side note, I’m fed up with NetworkManager breaking all the time on my ubuntu, and finally learned how to create a mapping in /etc/network/interfaces – http://wiki.saymoo.org/DebianNetworking)