While giving your computer as a hand-me-down to friends or family is always nice, you might not be aware that some of your data still exists on your computer which may be accessed using software applications designed to scan for deleted data.
If you're getting rid of your computer, East-Tec's DisposeSecure can clean your system of data which may still be accessible. The program will check each disk sector and remove current data by overwriting it with nothingness.