Xaro: I would refer you to page two and three of this thread on Boot N Nuke (or dban for short.)

Depending on the speed of your CPU and hard drive size, it may take time over write the data on  your tower, mini-tower, desktop or laptop.

I wonder how this would work if you have ASLR (Address space layout randomisation) enabled. As per the new Vista security standard. Yes, you can find the key, but its hard work.

Also why not just use peerguardian or something like TOR to thwart their tracking of torrents. If that fails you have drive encryption at your disposal in the form of a removable drive. If they trip the front gate beams or motion sensors, you can unplug the drive and toss it into your microwave oven, or dip it into a vat of sulphuric acid, or just toss it down the laundry chute. Oh wait, destruction of evidence is bad. Err, OK so you swap your external drive with another one. Just throw it into a box labeled "broken shit". Alternatively keep your arc welder handy, then just weld a hole through the drive. Tell them you were making modern art and that its in the eye of the beholder. Oh, you will also need a ferris beuler voice on the doorbell answering system to slow them down while you fire up the arc welder. If you are a real pro, you can disassemble the drive and remove the platters before they make it into your home. Tell them you were fixing the drive since it crashed. Oops. Once the platters are unaligned, my understanding is that its easier to kill all the mosquitos in Canada than to get it up and running again.

Plan B is to run a virtual OS inside another OS. Put the virtual OS in an encrypted volume. That is simple to do and a real pain in the nethers for your local boy genius to decipher. Even if they get the key off the RAM, you can have several drives with the same filename on it. Different key. That should slow down those knowitall agents of the law.

You can always just use your neighbour's weak WEP key to get cheap wireless that way. Then buddy up with some intrepid russians who will allow you to download movies, porn and the missile schematics that they stole from the US via a SSL encrypted connection. Pay them via a cayman island ceiling limited credit card linked to a false pseudonym paypal account that you signed up using a SSL Proxy in guatemala which you get to via several routes that you manually put into various cisco routers that the dumbo sysadmins left running with the default password or an old IOS.

Oh wait.... you could also just go to the video store. Then rip the stuff, share with buddies over external drives. Undetectable. Oooops. Yes it costs more. I know that part. Except for Khazakstan interestingly. Their bandwidth is massively expensive.

The other major alternative is to fly to china. Get every movie ever made for a few dollars (since you cant buy the real thing even if you wanted to. I believe thats only for the export market). Watch them till you are sick and then come home. They cant take that from you you know.

Now the big question is ... why dont the RIAA tackle China ?
Maybe they dont have words for "intellectual property" in Mandarin or Cantonese.

With all the talk of data erasing tools, i'm suprised nobody linked this one: http://www.heidi.ie/node/6
Eraser.
Simple, open source, free.

It goes through the process outlined in Peter Gutmann's paper.

It *theoretically* makes the data 100% unrecoverable in any way shape or form, without damage to the disks.

From the site:

Isn't all this work pretty much redundant when they get your isp logs?

ISP doesn't know what you were downloading. Only when, and from where.

To know what it was, they would have to keep a cached copy of all net traffic ever. that is impossible, Since even I would probably have several terabytes all to myself by now, I have a hard time storing all of MY OWN data. multiply this by like, 900,000 at, say. 10 tb a year each (keep in mind, this would include just regular web page surfing and stuff  like youtube) that is a mindboggling amount of data for my city alone. The logistics of this is insane, so unless you specifically are being monitored, don't worry about the ISP's logs too much.

My solution is just to keep all my drives encrypted, when the time comes, I can run a script which will unmount all drives, and then begin formatting them. even though chances are they wouldn't be completely destroyed before someone got in the door and stopped it, the data would still be inaccessible, since enough of the drive would be erased making it unmountable, and even if it was mountable you still need to defeat the encryption. if they ask me what the password is, well i've left the drives mounted for so long, I can't remember what it is. Sorry officer.