Darik's Boot and Nuke: sterilize an old computer prior to donation or sale

I've found a home for an old machine, but how do I wipe the drives? I'd read a while back about this utility, and Google found it for me. I'll report on how well it works.

Darik's Boot and Nuke

Darik's Boot and Nuke ('DBAN') is a self-contained boot floppy that securely wipes the hard disks of most computers. DBAN will automatically and completely delete the contents of any hard disk that it can detect, which makes it an appropriate utility for bulk or emergency data destruction.

I assume by "emergency" destruction they're referring to a scenario I'd rather not think about too much.

Update 10/10: Seemed to work perfectly. Downloaded the zip, ran the executable that creates the floppy, rebooted, hit enter, selected drives to wipe, accepted the default (medium security). Took about two hours to wipe two drives simultaneously. Of course I don't know how good the erasure is, but I'm betting it's pretty good. I trashed the diskette, I've no need to keep a 'loaded diskette' in the house. I give away a machine every few years.

kw: Linux, diskette, disk, wipe, clean, purge