In my second installation of XP in a week (don't ask), I opted to installed ICQ Lite instead of the normal ICQ "Pro" version. So, far, I like it well enough. It's lightweight, and doesn't have all the silly options of the Pro version, but it runs in less than 8MB of RAM (vs. nearly 20M for ICQ Pro). The only thing it's lacking currently that I really like in ICQ "Pro" is the invisible options... Anyway, you might try it out, if you're fed up with having that silly 20M process on your machine, like me... (oh, and it's ad-free out of the box, so no having to rename .AteBrowser and deleting the icqhttp.dll file to get rid of ads.)
http://www.icq.com/products/icqlite/whatsnew.html
