I've always wanted something like this... although Google had nearly, mostly satisfied my technical questions (after hours of intensive search & hair-pulling).
Check out their screenshots: http://krugle.net/product/ (still in beta)
A (nearly spam) comment to this post mentioned codefetch.com, an earlier service providing search for codes. I just gave it a try, and was amazed to see 'direct results'! At the risk of sounding like spam, it did seem super-instant, a little too encouraging to copy-paste! Perhaps I've grown accustomed to following thought processes that normally go around a problem thread in a mailing list archive...