CCAN (http://ccodearchive.net/) is a collection of open source C code libraries and modules loosely modeled after the CPAN project for Perl code. More than half of the code comes from such OzLabs luminaries as Rusty Russell and David Gibson. Code ranges from simple portability wrappers to sophisticated systems libraries. CCAN includes a strong lint and testing tool with code coverage feedback, to help people write consistent and robust code. Best of all, expert code review is available on the friendly mailing list.
I began contributing to CCAN late last year. Here’s my list so far: