Abbriator cmjooonss.
Emotium generates emoticon packs for Adium.
Emotoquy generates emoticon packs for Colloquy.
Pendantifier lets you correct people in the most infuriatingly smug way imaginable. Please don’t.
YukariBoard lets you create Azu-flavoured chalkboard writing.
YukariBoard Favourites contains the best ones I’ve seen. Yes, I look at them.