Story

use the secure-delete package instead of something like DBAN or another Windows wiping tool.

"Description: tools to wipe files, free disk space, swap and memory
Even if you overwrite a file 10+ times, it can still be recovered. This
package contains tools to securely wipe data from files, free disk space,
swap and memory."

Once DBAN was recommended by many, but it appears to have been snatched up
by a company and depending on many factors, including whether or not the
company involved is located in the US, I'm sure it's been hobbled by now.
I would not trust DBAN.

I would not trust other Windows wiping tools for many reasons, one because
you'd be using Windows, two I've heard of these programs being modified by
malware after installation and rendered useless. They will go through the
motions but not wipe everything or in some instances, wipe nothing!

use 'hexdump -C drivenameyouwiped | less' following the wiping using
secure-delete.

you can also use the 'dd' command to add additional wipes if you're
paranoid.

before you feel your job is done, i'll just leave this here
for your consideration:

---DCO and HPA (Host Protected Area of HDDs)---------
http://en.wikipedia.org/wiki/Host_protected_area
http://www.forensicswiki.org/wiki/DCO_and_HPA
http://hddguru.com/software/2005.10.02-MHDD/
http://hddguru.com/software/2006.01.20-Hitachi-Drive-Feature-Tool/
http://hddguru.com/software/2007.07.20-HDD-Capacity-Restore-Tool/
http://www.itsecure.at/hparemove-v0-2/
http://www.sleuthkit.org/informer/sleuthkit-informer-17.html#hpa
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