NetHack

One can get quite addicted to it. If you're german speaking, I really can recommend this guy, having posted almost 100 "let's play videos" covering this great roguelike game.http://www.youtube.com/user/irrenhaus3
Here's an example video from him:

SATCOM

I'm quite interested in the field of SATCOM. A good starting point for the german speaking folks is here: http://www.satellitenwelt.de/uhfmilsat.htm
From there you'll find a couple of useful links to people who actively maintain their pages and even put some audio snippets online, most interesting for me were:
http://www.solarix.net/category/satcom/  (audio recordings)
http://satcom.tonnarelli.com/ (same here)
http://www.uhf-satcom.com/ (lots of frequencies and tech info)

The Cuckoo's Egg - Cliff Stoll

True story about an astronomer helping tracking down some hackers. I really recommend this one. Got mine recently signed by the author. Thanks Cliff!
He also produces some crazy zero-volume bottles. This link gets you there.

The PC Weenies comic

Have you ever checked out this regular?

He even draws custom ones for you if one e.g. want to surprise someone with an uncommon present :)