perftools: Libraries and tools that help you tune and debug your multi-threaded c++ programs.
coredumper: Gives you the ability to dump cores from programs when it was previously not possible.
sparsehashtable: An assortment of interesting new hash tables for C++ developers.
goopy/functional: This library brings functional language attributes to python.
http://code.google.com/faq.html
Google release new Site for Coders using its' APIs