3-D printer. We've got one at my school and I've seen several other designs on the internet but they all have a fairly small printing surface and are pretty impractical. My challenge to ben is to make a 3-D printer with a printing surface large enough to make cases for mods or any other cool plastic stuff you could think of. It should have a printing surface of at least 2' x 2' and it would be pretty cool if it could switch colors of plastic according to the colors of the part it is printing..
