I am slightly obsessed with the reprap, a rapid prototyper project that is very experimental. I want to build one myself, but my current skill is a few notches below something so ambitious, not to mention free time. But if Ben were to show us all how to build one I'm sure it would help. Plus it would give him a way to make small parts he may need for future projects, which would be ultimately cool.
You can learn more at http://www.reprap.org