I worked at a computer forensics company for a while. I liked how we'd always get in PDFs that were "password protected" using Adobe's encryption feature and 99% of the time the password would be a dictionary word that we'd find in a few seconds using our quite primitive password cracking software. Our clients paid us $100 per document for cracking passwords too.
By the way, the leading computer forensics product (EnCase) is buggy crap, with the worst proprietary embedded scripting language ever (which I was sadly forced to spend the majority of my time working in. our company billed clients $150 an hour for my services, and paid me $12 an hour). It's supposed to be typesafe with automatic memory management, but I could show you about a dozen perfectly innocuous-looking expressions that segfault the application, requiring a reboot (or in one case, actually corrupting the application files so you have to reinstall).