(Non-Computer) Science

SETI@Home I help find aliens! Or at least i run this client when i remember it. A great course to answer the most fundamental question of man - here's to hoping the answer isn't 42.
Astronomy Picture of the Day Explore our universe gradually each day.

Hardware

Hardware Book Information about all sorts of different ports, cables and interfaces. Need to connect your C-64 disk station to your parallel port, well this is where to go.

UserFriendly Follow life at a (not so) normal internet service provider.
WulffMorgenthaler Really screwed up cartoon with naked people?!? By two danish guys (in english though)
Abekat If you understand danish, this is a very funny "blog" type joke site.
Men In Hats Ill mannered men in hats talk badly about Life, Christians, The Universe, and pretty much everything else.
Punks and Nerds is frequently funny, but you really need to read it from the start to really appreciate it.
Joe and Monkey, a bit like Calvin and Hobbes, but with a mad kleptobot instead of Susie.
XKCD Geeky yet surprisingly dreamy, dealing with existentialism, love and regular expressions.
The Daily WTF Horror stories from the world of IT.

SlashDot.org If you are looking for news for nerds with biased discussions, flaming and server shutdowns - this is it!

Python Since discovering Python i guess that about 80% of the code i write is Python - try it - you'll love it. And by the way the only programming language with never-ending Monty Python jokes.
Dave Marshalls C Programming Great course for learning C programming, also includes a some *nix knowledge along the way.
C++ FAQ Lite Marshal Cline's excellent C++ FAQ - years of comp.lang.c++ knowledge in one place!
Googles Programming Languages If you like programming languages as i do, you'll love this page, it has everything from BrainFuck to Intercal :-)

Debian the Universal OS Can't tell you how many times the speed and integrity of this loosely knit group of about 9000 volunteers has surprised me with wonderful and creative solutions to complex problems. Needless to say i run Debian GNU/Linux. But am hoping that GNU/Hurd will be even cooler.
GNU Free Software rules! You can hate or love Richard Stallman, i won't take sides here, but everybody agrees that he has made one of the most significant contributions to the well-being of the software industry.

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