I wrote about syntax hightlighting in Ruby earlier. The Ruby Syntax library supports Ruby, YAML and XML out of the box. But it's also pretty easy to extend to handle other languages.
Since I've been writing my compiler in Ruby series and including a lot of x86 assembler, I ...
You may have seen that I'm posting a series about writing a compiler in Ruby. Here's a similar project, but compiling scheme to x86 asm. The page is well worth a read for the insights into various compilation issues:
Ur-Scheme: A GPL self-hosting compiler from a subset of R5RS ...