In 2009, some friends and I started thinking about building a RepRap 3D printer. Unfortunately, to build a RepRap, you first need another RepRap. Or you spend a significant amount of money on a commercial 3D printing service to get the necessary parts. Both variants didn't really appeal to me, so I started building a RepStrap (for bootSTRAPping the RepRap).
Since a friend of mine is a distributor for Isel aluminium T-slot profiles, I decided to use the highly versatile PU25 for the main structural components of my RepStrap/CNC mill/whatever. Since proper linear bearings are hideously expensive, I've browsed through my local hardware store and found some small drawer slides with ball bearings that fit perfectly (Hettich No. 00494, for future reference). Add 3 stepper motors (NEMA17) from eBay, M6 threaded rod as drive screws and a set of RepRap Gen3 electronics for control and voila: [picture to come]