LEGO Virtual Machine + Firmware Source Code project
This project is to make the LEGO VM and Firmware a bit easier to compile and tweak. You can download the whole thing via Git. More info here: https://github.com/mindboards/ev3sources
BrixCC for EV3
Currently undergoing heavy development, BrixCC is being made ready for the EV3. Go check it out and play with it here: http://bricxcc.sourceforge.net/test_releases/
Lejos for EV3
You can run Java on your EV3 with relative ease. Mark Crosbie has written a Guide for getting it setup on your brick.
EV3 RGF support in ImageMagick