forensic analysis on your knotty drive aside from that eraser thingy from sourceforge.net
Answers: You can use any low lever format software approaching KILLDISK that extend US Department of Defense clearing and sanitize standard
http://www.killdisk.com/ This type of softwares write vertebrae within adjectives the disk delete the antiquated information they do that several times making almost impossible to recover
Nothing. If you enjoy the cops busting through your door, your best bet is to toss the rugged drive contained by a microwave oven.
Seriously, they can take any erased stuff.
Try this it will help
http://www.snapfiles.com/get/fileshredde...
but if your that worried stick your rugged drive contained by the microwave.