Here are some links to other great sites on the web.
NeoZones - one of the most active sites in the QB scene
Future software - another great QB site
Nightwolf Productions - and another one, home of the QB Times, for whom I sometimes write articles
SonicBlue - another one that deserves being mentioned
C&C: Tiberian Sun website - one of the coolest RTS games to ever appear
Starbreeze - check out this cool game they're working on... beats quake3 if you ask me
Winzip website - the greatest utility of all... you'll need this to open the compressed files that you can download from this site
ICQ website - another great invention, if you haven't got it already, then go get it now!