One of the usually propogated myths about computer hard drives is that in order to wipe the data clean, the drives have to be overwritten with zeros and ones using various methods multiple times.
One internet site is attempting to debunk that myth with a simple challenge. They took a drive and overwrote its contents with zeros ONCE. Now they are offering $500 to any professional data restoration company that can recover the data.
From the website:
Q. What is this?
A. A challenge to confirm whether or not a professional, established data recovery firm can recover data from a hard drive that has been overwritten with zeros once. We used the 32 year-old Unix dd command using /dev/zero as input to overwrite the drive. Three data recover companies were contacted. All three are listed on this page. Two companies declined to review the drive immediately upon hearing the phrase 'dd', the third declined to review the drive after we spoke to second level phone support and they asked if the dd command had actually completed (good question). Here is their response... paraphrased from a phone conversation:
"According to our Unix team, there is less than a zero percent chance of data recovery after that dd command. The drive itself has been overwritten in a very fundamental manner. However, if for legal reasons you need to demonstrate that an effort is being made to recover some or all of the data, go ahead and send it in and we'll certainly make an effort, but again, from what you've told us, our engineers are certain that we cannot recover data from the drive. We'll email you a quote."
I am posting this because I have always believed that I needed to wipe drives multiple times as well, and I would love for this to be true. It would save a lot of time for when I have to turn in my laptops and get new ones. I always spend time wiping the drives to remove all personal info.