Disk sanitizer

[Jared Anderson]

I know this topic has come up before, but I am too lazy to look into the 
the archives ;)

I'm aware of:
shred -vz -n 6 /dev/hdx

Also dd:
dd if=/dev/zero of=/dev/hdx bs=4 count=?

I've seen some bootup floppy stuff, and I know most live distros have 
the above mentioned tools; however, are these the most efficient 
(meaning fastest) methods to cleanse a disk to dod standards?  I need 
one opensource solution that works for x86 and PPC archs.

TIA

Jared