What ICQ the client you use?

Pidgin (for ICQ, MSN and Yahoo contacts, wish they would agree!)
Pidgin. Been using it for ages. It annoys me at times, but it's about the most usable one for me I've found.
I am a lot of years used licq -> centericq -> sim-im. Now switched to kopete, because i using KDE, kopete is the part of KDE and i have confidence in him future. And it support ICQ and XMPP proto (and many other) simultaneously