At our office, we are disposing of some old servers. Carol has arranged to have the drives "cleaned" by some sort of process. I've taken the opportunity to do the same with some old computers around our house. As to the computers at our house, I removed the hard drives before sending them off. I am not sure what I will do with the drives, but I have in mind to use an electric drill and make a few holes.
Carol, as our office adminsitrator, keeps an eye on a list serve sourced by a web publisher called Technolawyer. She sent me this post:
For anyone interested, there is a free program available at dban.sourceforge.net that will let you securely wipe an old hard drive. The site doesn't look like much, but this program has been around for a long time and I have used it many times. Everyone should do it before you think about selling a computer on ebay or donating it to a school. A simple format does not delete any data on a drive, it just marks the area as "usable." Because of this, it is amazing how much personal information (cc numbers, ss numbers) can be recovered from old drives and computers that are sold on eBay every day.