I've purchased a hard drive docking station that holds 2.5, 3.5 SATA and IDE hard drives. I want to erase the information within the hard drives I've collected and start selling them. There are many free data-erase software programs out there but I want to have something that says it is certifiable. I don't mind paying for the software to allow this but many of the ones I have researched say they are only good for use 3 times and then you must buy the software again (this is no good, as I have 60 hard drives). Anyone knowledgeable about this?

Here is an article 5 Free Programs to Completely Wipe a Hard Drive