[ubuntu-uk] Securely delete data

[David Smith]

Supposing I have a netbook loaded with Xubuntu that I want to sell on (shameless plug, eBay item 290811097220).

If it was running a Microsoft OS, I'd create a new user, remove the old one, look around for and delete any data lurking in the root and find an app (CCleaner for example) that'd do me a couple of zero-fills.

Is it a good idea to create a new user and remove the old one to prep the Xubuntu netbook?  And is there a CLI or GUI app can I use to zero-fill?

Cheers,

DS