MIT student ChArLeS wrote in with his latest project, a 3D printer.

My first entry into the DIY 3d printer game is tongue-in-cheek christened Make-A-Bot because of the numerous design inspirations it features from the similarly named commercial kit machines. It’s a Fused Deposition Modeling / Fused Filament Fabrication type machine that draws successive layers of an object using a continuously extruded molten plastic fiament. FDM/FFF creates structural parts that are usable immediately. Most of the deviations on this machine from existing open-source kit machines are in the interest of exploration. The work envelope is designed to be larger and taller, and the mechanics are fully custom. The machine also features some small design experiments such as flexure-mounted guide bearings and a fast-travel Z-axis. Otherwise, it uses stock Makerbot and RepRap electronics and the extruder head.