I've been pretty busy with Ph.D. stuff, but a couple weeks ago I
tinkered around with a fairly new tool for doing procedural CAD
development:
http://www.pythonocc.org/
http://www.opencascade.org/
It's a bit of a pain to install, but if you're proficient with Python
and interested in doing procedural mechanical design, it's worth
checking out. One of these days I hope to port the Rhinoscripts /
VBScripts I wrote for generating keys over to pythonocc. Python is a
much nicer language to work in, and both python and Open Cascade are
free/open.
Cheers,
Drew