Properly wiping a hard drive ?

[JD]

  On 10/08/2010 12:31 PM, Linuxguy123 wrote:
> I bought a hard drive and wrote a bunch of information to it as an
> external drive only to find that it won't fit in my laptop as an
> internal drive.
>
> How do I absolutely destroy all the data on the drive so that I may
> safely return it to the retailer for a refund ?
>
> Thanks
>
This was discussed at quiet some length in the thread
  Scrub free disk blocks
See URL
http://lists.fedoraproject.org/pipermail/users/2010-August/subject.html
  Scrub free disk blocks

Even though the subject is titled for free disk blocks,
the tools mentioned also apply to securely erasing
the whole drive.
The command line utility wipe
could be  used to wipe out the entire drive.
Of course, if you are really worried about the
personal and proprietary data on the drive,
you could either destroy the drive altogether
and forget about a replacement, or if you have
access to a powerful electromagnet of a few
million gauss, then subject the disk to that
magnetic field moving it around the electromagnet
several times :) :)
Of course, I have never done it because I do not have
such a magnet.