Icq2go, flash based icq service comes quite handy.

I just found out today that the good old chat application called ICQ has a flash based web frontend. In real english that means that you go @ http://www.icq.com/icq2go/ and you click the start icq2go icon and a popup window with an icq message center appears.. If you are a member of the network in an internet cafe that doesn't offer icq or you simply don't want to install the software itself all you have to do is visit the page and voila!
New members can sign in on the spot so no hassles there..