Many PC users are still under the impression that deleting a file removes it from the hard drive. It does not. The data is still onboard, and savvy banditos can access it if they get their hands on your drive. That's right, your account numbers, passwords, user IDs, credit card numbers, you name it.
How to handle?
Surf over to Kill Disk. They have a free product that will "kill" your disk, or remove all data. There are two levels: one pass "kill" (free download), and high level, military-style multi-pass, priced from $39.95 to $59.95.
The free version is a no-brainer, and if you're hesitating at the tariff on the high-level versions, we have two questions for you: 1) how much is your peace of mind worth? and 2) how much will it cost you in time and effort to reclaim your life if all your confidentials fall into the right hands?
Can't happen to you? Happens to the U.S. government even; students found sensitive U.S. defense contracts -- in Ghana!