To clear up some myth:Whilst I fully support the idea of using the Gutman 35 pass method of erasure, it is over-kill as it takes substantially longer than other methods. Nobody in the world has ever recovered data which was erased even using 1 pass contrary to popular belief, this idea they can recover information from the disk was theoretical back when they have entire hard drives less than a few megabytes large and so it was easier to carry out work on them. However these days, disks are far more dense by the order of several magnitudes and it would be close to impossible to recover anything from them which has been overwritten. I myself use 3 passes most of the time and use 35 passes on something I REALLY need to delete. However, if you've already got your full hard drive encrypted, a simple 3 pass erasure will make it far too difficult to ever recover.