A neat little header file with commonly-used macros for Objective C programming:

GNUstep-style ASSIGN(), DESTROY() and CREATE_AUTORELEASE_POOL() for easier accessor writing, clearing and destruction with less typing, easier NSThread method writing, a UKLog() macro that gets turned off in release builds and prefixes messages with the method/function  name, and a PROPERTY() macro that type-checks method name strings for KVO.

Official UKHelperMacros web site

Official UKHelperMacros repository