Since I don't need emoticons and speak in complete words (are and you are three letter words, abreviating them only makes you look stupid) I've stuck to ICQ. I have a copy of 2000b on cd with other apps I use frequently so that when I wipe my hard drive (about once a year) I don't have to hunt them down. Why use such an older client? Simple, my database is stored locally and not on some AOLTW server.

As for the ads on ICQ, just use ICQ+. The skins kill any ads you are supposed to see and there are currently thousands of skins on various sites.