Here is our selection of useful links.

Programming related links
Microsoft Developers Network - The one resource for win32 API coders.
System Internals - Great site hosted by some really mean programmers. =) Class A Windows utilities.
Software links
UPX - THE executable compressor.
MJSoft - The installer used for Netmon. Small and efficient
Tweakfiles - Lots of goodies when it comes to tweaking, optimizing and monitoring software.
Emulation / Gaming related links
Retrogames - The number one emulation news site.
Back to the roots - Amiga nostalgia deluxe! Features heaps of Amiga demos/games/pictures/sound modules.
The Underdogs - Without a doubt the best site for "old" classical games (abandonwarez).
Networking related links
WPacket - A kernel mode packet driver which allows some funky stuff, like direct packet capturing.
Mike @ Datanerds - Windows ports of useful lowlevel network utilities like Snort and Dsniff.
Snort - One of the best NIDS:s (Network Intrusion Detection Systems).
Packetstom - Good site with heaps of network security information and tools.
Music related links
Winamp Homepage - IMHO the best MP3 player for Windows.
Other links
Google - Very useful search engine
Altavista - Also a very useful search engine