I've seen quite a selection of software on the market with claims of getting rid of the data for good but upon further investigation it's not 100% reliable.
We're only as reliable as the solutions we offer.
The obstacle here is that, apparently, leasing companies don't care to have hardware returned to them with the HDs in 1000 pieces.
I have a good friend that runs an IT surplus business and he was able to offer a little assistance. He just happens to own a shredder:
http://www.youtube.com/watch?v=5uc-tpvAxkw
Once they shred the HD they provide a certificate of destruction as well as an old HD to slap in the box before heading to it's final destination.
This month I'm focusing on offering more of a selection in my solutions. i.e. "Would you like the red or the blue?" instead of "I suggest the Red" The idea is to offer a Yes or Yes instead of a Yes or No.
This will be an offering at the beginning of my hardware leases from now on. I'll be offering this or the standard overwrite kit.