A Cocoa / Objective-C wrapper around SQLite
Three20 is an Objective-C library for iPhone developers
Easy to use CFNetwork wrapper for HTTP requests, Objective-C, Mac OS X and iPhone
ASIHTTPRequest Documentation - All-Seeing Interactive an easy to use wrapper around cfnetwork http api, mac os x & iphone
A conforming Objective-C WebSocket client library.
JSON (JavaScript Object Notation) is a light-weight data interchange format that's easy to read and write for humans and computers alike. This framework implements a strict JSON parser and generator in Objective-C.
SBJson for Objective-C :: http://sbjson.org
An XMPP Framework in Objective-C for Mac and iOS
Objective-c code Apple style documentation set generator.
Gentle Bytes - Crafting useful software
A few code snippets from my Xcode arsenal
Simple Objective-C wrapper for the keychain that works on Mac and iOS