From DBAN’s site:

Darik’s Boot and Nuke (“DBAN”) is a self-contained boot disk 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.

Go to DBAN download page and get the stable release for floppy disks and USB flash drives. The file has an exe extension but it is just a zip file.

Unzip the exe file:

$ unzip dban-1.0.7_i386.exe

Loop mount the .ima (image) file:

# mount -o loop dban-1.0.7_i386.ima /mnt

Copy the kernel and the initrd to /boot:

# cp /mnt kernel.bzi /boot/dban_kernel.bzi
# cp /mnt/initrd.gz /boot/dban_initrd.gz

Edit grub menu.lst file in order to add an option to boot DBAN:

label DBAN
kernel /dban_kernel.bzi nuke="dwipe --autonuke" root=/dev/ram0 init=/rc console=ttyS0,115200n8r
initrd /dban_initrd.gz

I used / instead of /boot because /boot has its own partition on this machine.

The file syslinux.conf that comes inside the floppy image lists the options you can pass to the nuke argument.