Note: as of iOS5, this is no longer needed. NSURLCache now properly caches objects, as long as the Cache-Control header is set. This is a fork of https://github.com/rs/SDURLCache, that drops iOS3 and uses ARC. The changes to use GDC and the improved date parsing are also a potential speed-bump, although I haven't gone through the effort to actually benchmark this. On iPhone OS, Apple did remove on