RepRap
Stumbled upon RepRap. Seemed interesting. Before trying to build my own, however, I thought I'd have a look at their software.
So, I downloaded the thing. Then had a deep sigh, as the bloody thing uses Java. And they still live in the middle ages, since the 'Linux version' ships with some .so files for i386 only. Fidgeting around until I find the right version of the amd64 .so file seems somewhat hard.
I think I'll pass on that one, for now.
Whenever someone tells you that 'java' is the right solution if you're looking for 'portability', they're on crack. Seriously. I'll have C and POSIX any day, kthxbye.
There is a python alternative called skeinforge used by a good few reprappers. There is also a forum section or two on the http://reprap.org where these things can be discussed and even fixed! Ralith (in #reprap on freenode.net) is even developing a minimalist C RepRap driver. No doubt he'd welcome your input.
Use of Java in driving Arduino/Sanguino can also be circumvented if desired. Meanwhile, you can always boot off the RepRap liveCD.
Vik :v)