When you're doing lots of quality assurance testing for other companies, security becomes an important component. No one wants to lose business because they accidentally leak product information, even after the testing is complete. To make sure you're erasing your hard drive securely, you can try Darik's Boot & Nuke (DBAN). DBAN provides a self-booting disc which allows you to securely delete everything off of a hard drive, and makes the data unrecoverable including to current forensic analysis methods. DBAN is a free download, although they also offer a commercially supported version (EBAN) which includes the necessary support for compliance with SarBox, HIPAA, and FISMA.The same software also works for those of us who want to clear our hard drives before recycling or selling our computers. Don't want the new buyer to get our bank or credit card info.