Eric Furman wrote:
It can't be done. it's an urban legend, AFAICT. http://www.nber.org/sys-admin/overwritten-data-guttman.html Which references Gutmann's paper which started all this...
Of course I'm sure a tax analyst (http://www.nber.org/vitae/vita184.htm) knows more about data recovery than a security researcher with a history of researching overwritten-data-retrieval (http://www.cs.auckland.ac.nz/~pgut001/).