Howdy!
I'm looking to see if one of these already exists, or can be easily built. I'm looking to make a bootable USB key, that when booted from, will immediately erase all the drives connected to the machine (except itself). It can be done via simple "quick format", or a regular format. It is not necessary to make the data non-recoverable, just need to make sure the drives look empty.
It is important that there be NO user interaction. Simply insert the key, have the BIOS boot to it, it erases the drives, then reboots the machine.