Are you on the hunt for some code on the Internet? There's a free tool out there from Krugle, Inc. called Krugle. Yes, that rhymes with Google. Krugle searches and indexes code from public software repositories from the likes of Apache, Debian, Mozilla and SourceForge.net.
Krugle has parsers for more than 40 languages allowing syntax-specific searches. So you can use code features like function calls, class definition, even comments in search queries. Queries support broad or exact matches and allow code tokenizing. Filters are available to hone in on specific projects and sites. And if you register, there are collaboration tools that allow you save your search to a "code space" where you can comment on a code file or project and share it with others.
Last but not least, Krugle has IDE plug-ins for Eclipse or Visual Studio and browser plug-ins for Firefox (version 1.5, 2) and IE (version 6 and 7).