Scrub free disk blocks

[Bruno Wolff III]

On Sat, Aug 28, 2010 at 08:36:48 -0700,
  JD <jd1008 at gmail.com> wrote:
> There is nothing you can do about
> relocated bad blocks.

You can use secure erase. That is suppsed to try to do something with those.
You can also use encryption in the first place.
It will be some work to get from where the system is now to a state where
secure erase has been used and stuff is put back on top of an encrypted
block device, but it can be done.