Security assessments are always interesting. I know, I do them all the time. You can never guess what you'll find when you're investigating a breach and a federal agency recently found that to be true.
Human Resources and Skills Development Canada lost a USB key with personal information on some 5000 Canadians. As is the case with things you're looking for, those are precisely what you don't manage to find. While investigating the missing memory stick the agency discovered the disappearance of an entire hard drive containing personal information on more than half a million student loan borrowers.