RebolLexer is a project mainly written in Python, it's free.
ExtendedRegexLexer to colorize REBOL code using Python's Pygments
I've made this code because I was missing REBOL support in Pygments' colorizer. It's older then REBOL3 so it would require some small updates.
I must say that I'm REBOList, not Pythonist and this was my first and so far last Python code.