This is the start of an on-going, updatable, list of on-line resources regarding parametric-geometric scripting.
Initially, it will focus mostly on rhino and processing. Other programs will be included according to each and everyone's interests.
Yimei has already mentioned the reconstructivism people. This is a site that seems to be in line with sites like dritsas.net and design tooling.
Some scripts are made available on these sites, but the descriptions of the processes seem to be more complete, at least from a first approach point-of-view.
materialsystems has a few scripts, the theverymany.net keeps going strong and there's still hope of seeing these guys' scripts one day...
The Rhino site has this page , and this MIT resource still seems quite helpful (I wonder if there are other MIT pages).
Now, regarding processing and the like, this Yale resource seems quite good, as well as this MIT one, and we already mentioned complexification.net