Deleting HDD

I want to random data overwipe my HDD several times, to be leet.

Any programs you'd recommend?

>>5 fail
A wiping script would be trivially simple:
#!/bin/sh

cat /dev/urandom > /dev/hda1 but it wouldn't sufficiently erase the magnetic traces left on your hard disk that can be used to recover your child p^H^H^H^H^H^H^H sensitive data.