Have you had a chance to look at Google Code Search? It truly will help you find function definitions and sample code by giving you one place to search publicly accessible code through the use of regular expressions and language and filename filters, but this is taking a backseat to what Code Search can really do…like discover vulnerabilities in the indexed code and make you laugh.
How’s about this? Discover what coders are cursing about. Find complaints about stupid users. Realize that you aren’t the only coder who hates their job. And find out who is coding drunk or who begs forgiveness from the coding gods. This is just the fun stuff. Find “real” vulnerabilities at kottke.org.