Hacker is a card-based game made by Steve Jackson Games. It was inspired by a
raid by the secret service, where the SS took their computers, modems, disks, and a pocket calculator. Allegedly, it was because they thought the rules for GURPS: Cyberpunk was an actual manual for hacking, and, additionally, one of the employees was a member of an actual Hacking group.
In any case, in the couple years after the raid, they got most of the stuff back (with difficulty), although a lot of it had been broken. As a result, Steve Jackson Games had to lay off half their employees and narrowly skirted bankruptcy.
After all was said and done, they decided to make a game out of it. The game is called Hacker. And it rocks.
Basically, you start with a small network in the middle of the table. The computers are connected to it, and some of them are "indials", which means you can call them directly. You have some hardware in front of you that can be upgraded for more or stronger hacks. You can start by attempting to hack any of the indials. When you're in, you have control of it and can connect to computers nearby. Multiple people can hack the same system, but if there are too many on a single box the admin might notice and "clean house" (ie, attempt to kick people off). You can have user access or root access to each box (you get more bonuses with root and it's harder to kick you off).
There are a lot of optional rules, including the introduction of viruses and worms. We haven't played with those yet.
All in all, it's a crazily fun game! We played two rounds yesterday for the first time (me and two buddies) and had a blast!
In the second game, we got right to the end, I was one turn away from winning. Then the guy beside me (who's also on the verge of winning) plays a card that re-structures the network, and he broke my connection between my dialin and the pentagon, which meant I lost access to my accounts (although they were still there, I couldn't use them). Then he decided to narc on me, but he blew his roll (rolled 1 1 on 2d6!) and got raided, which means he lost all his equipment. Luckily, he made his roll not to get busted (which means he got to keep some stuff), until I played a card that forced a bust. Ha!
Then, on his next turn (I naturally didn't win and the third guy was way behind), he pulls a "raid" card, which he plays on me! So I get raided, and lose all my stuff! Gah! So suddenly, me and him are back to almost nothing, and the third guy, who was nowhere close to winning, won!
But yeah, it's so much fun. I couldn't recommend it more!