Adium is a free and open source instant messaging application for Mac OS X, written using Mac OS Xs Cocoa API, released under the GNU GPL and developed by the Adium team. Based on the libpurple protocol library, Adium can connect you to any number of messaging accounts on any...

































































It's pretty much the same concept: threaded conversations for asynchronous communication, it's not as sophisticated as some aspects of Threads, but I like the better contrast for improved readability on Twist, while Threads tries to look pretty (it does), but sacrificing legibility and scanability for the looks.