Disk wiping in Linux

[Dr. Evil]

This may not be quite the right forum to ask, but I'm not sure where
else to ask...

Are there some disk wiping programs for Linux, which overwrite all
data on a disk a few times, so it can't be recovered?  Ideally, this
should be an option on the mkfs command, like mkfs -w /dev/hda1.  mkfs
has a -c option, but that doesn't do it, I think.

Thanks