Previously I have used absolutely evil C Preprocessor macros to generate code; this is a new experiment in using Ruby to generate such code. The idea is that this project can generate mostly-filled out code for you to use, but providing more customisability than something the preprocessor dragged in.
See the wiki for a bit more information about this project and capabilities.
It's a gem now! Installation is as easy as:
[sudo] gem install conyard
Patches and suggestions welcome!