The reason you want to securely wipe a drive before donating it, or selling it on eBay is that if you don't, the potential for the next owner of your equipment obtaining your financial records, or finding your secret stash of porn vids is pretty good. Simply formatting your drive isn't good enough to prevent this, as most of the data still exists on the drive. The only way you can make sure people can't recover that data is to over-write the drive multiple times with random 1's and 0's.
Now that you have a basic idea of what the show is about, here is episode two of Tech Chop!
What do you like to use to wipe hard drives? How many passes do you usually do? Let us know in the comments!