These are a selection of links that I use daily, or that are good examples of the best and worst of the WWW.
 

Internet-links

Mozilla The best browser there is!
W3C The WWW-standardisation authority
HTML-validator Check if your site is HTML-compliant (mine is)
RIPE See who owns a european IP-net
ARIN See who owns an american IP-net
APNIC See who owns an asia/pacific IP-net
LACNIC See who owns a latina/carribean IP-net
Hotmail Well... free crappy e-mail, but I suppose you knew that
Nunames Get your own .nu-domain!
What webserver? Check what webserver a specific site is using
Google Google is your friend...(?)
Wayback Machine Remember what your homepage looked like in 1995? The Wayback Machine Does!

Underground

Flashback The home of freedom & underground

General/Funstuff

Internet Movie Database Everything you want to know about all the movies ever made!
User FriendlyDust Puppy Now defunct but hillarious comic-strip for people in the IT-business 
MAME Multiple Arcade Machines Emulator. Play 1942 or Zaxxon on your PC!
Darwin Awards The most stupid ways people have managed to get themselves killed... hillarious!
Currency Converter Universal Currency Converter
Homesick? A Swedish grocery-store online that takes international orders
Google Earth Even better way to view of the earth from space
Everything2 WIKI-style encyclopedia
Wikipedia Even better WIKI-style encyclopedia
Freekick Best Football Manager Game Online

Computers

IDG/Sweden - Computer Sweden The #1 IT-newspaper in Sweden
Tom´s Hardware Hardware heaven
Slashdot News for Nerds - Stuff that Matters!
Dell The best PC-manufacturer around (unless u build your own)!
Filext (1) Find app associated with an "unknown" file extension
OpenBSD Free, Functional & SECURE

MP3/Media/Utils

Direct Connect The fastest P2P Network
DC++ A better DirectConnect client
Daemon Tools Why burn .iso's when you can MOUNT them?

Sci/Fi

Babylon 5 My favourite Sci-Fi show