Every so often, you need a script that’ll wipe a disk quickly and effectively. Introducing… Wildfire (named after The Andromeda Strain). Warning: this script won’t prompt to confirm your actions, so be careful!
Wiping is a two stage process; 1) run diskpart to delete the partition structure, and then 2) run sdelete (Mark Russinovich / Sysinternals) to securely wipe the disk (single pass for maximum speed).
Optionally, the script can also self-destruct (if so required) – just uncomment that line.