Here's a random collection of links that'll hopefully inform/help or amuse you.

Entertainment:
Bash.org - A site full of IRC quotes, can keep you amused for hours.
CAD Comic - An amusing web comic, or at least it used to be, the authors gone a bit too much into the amature dramatics, the sillies are sometimes chuckle worthy.
Nuklear Power - The Home of the 8-bit Theater Web Comic, very amusing if you know what's going on, if anyone does.
SimonG - A great personal website so it qualifies as entertainment not a friends site, loads of content, most of it amusing.
VG Cats - Another web comic, with web-comics designed to make a point about something vaguely video game related, that or just be DAMN funny.
XKCD - My favourite web comic, but that's because it's geeky without being nerdy.

Gaming:
Steam - The delivery system and gaming network of Valve and it's games (Half-Life 1 & 2 and its mod), if your a fan of fps's you should already have this.
Unknown Worlds - An indie games development company, an inspiration to people like me, currently developing the exciting looking Natural Selection 2.
Black Mesa - A gorgeous looking source mod, still underdevelopment! Worth keeping an eye on.

Media Players:
Winamp - My media player of choice, very good. Only problem is it doesn't seem to be able to play the tracks off enchanced music CDs.
K-Lite Codec Pack - This gives you back media player classic which can then play quicktime, real media and random stuff like mobile phone codec, without having to install all the media players under the sun.
Real Player - This can play the real media formats which are tiny! Other than that it's horrible, all of it, yuk.
Quicktime - You play iTunes and certain types of movie with this, which you can't do on the other players...
Foobar - A light and functional media player (or so I'm told, I've not bothered to test it yet).

System Ultilies:
Anti-Virus:
Avast! - Free Anti Virus software and I really recommend it, it's better than all the anti-viruses I've used including some you have to pay for, although it will kill your start up time, and can sometimes freeze when it decides to update before your computer has finished starting up.
Anti-Spyware:
SpyBot - aka SpyBot Search & Destory, a great free program that searches your system for spyware and adware and deletes it. (Although it's best to check out the details of each detection, it's quite strict, sometimes overly so).
Firewall :
Zonealarm - This is the best free firewall I've found, but it isn't perfect, if you just want it for browsing and e-mail it's great, if you want to play online games however I recommend buying Norton Firewall.
Graphics Card Drivers:
Omega Drivers - A great set of unofficial drivers for Nvidia and ATi cards, if you're having problems with the official drivers, give these a try (some cards can get a nice FPS boost too).

Chatting:
MSN Live Messenger - This is a nice messenger program, almost everyone uses it and it's interface isn't annoying (unlike AOL Yahoo and ICQ which are NOT listed here), made even better by MSN Plus!
MSN Plus! - A plugin for MSN Messenger that makes it even more functional with useful mIRC-like commands which are useful if you're a mIRC user or not! If you have MSN Messenger get this.
Web Messenger - This is a version of MSN that works through your internet browser, perfect for work or similar places where you don't have access to regular MSN Messenger.
mIRC - The best windows client for using the Internet Relay Chat network, if you've never tried this, do try it, easy way to chat to huge numbers of random people (but be careful with your personal detials ofc).

Misc Links:
I'm Gonna Bite you IN THE ASS
Team-KB - The Multi-Gaming Clan that I'm a part of! I don't play with them that much anymore though =(.
PUB - Another Multi-Gaming Community, I'm a part of, though I only play CSS.
Google - Best Search Engine, if you want something search for it here and you'll almost certainly find it (if it exists, for example real pictures of pink tigers or alien space craft maybe u hard to find, though if you do an image search for either you'll probably find some porn).