This is a DIY project inside a DIY project--total DIY awesomeness. This router automatically re-routes its rout, ensuring a precise cut for any project. After a frustrating woodworking project gone wrong, some MIT students wrote a program that continually creates a two-dimensional map for a router. The user only has to be accurate within a quarter inch.
It's better than a CNC router because it can cut anything, not just items that are smaller than itself. You can read more about how the students did it here