Ingredients is a free browser for Apple's documentation. You can:
Ingredients is also open source and available on GitHub
Try out Ingredients 1.1 Beta 1: Tabs, Click-to-Copy methods and much faster startup times.
Ingredients requires an Intel computer running Mac OS X 10.6 or later. Also requires the OS X Developer tools or iPhone SDK. 32-bit Macs are currently not supported, but this will be fixed in a later version.