Back in 2012, the FBI nabbed Jeremy Hammond, the most wanted cybercriminal in the US, at his home in Chicago. And until now, no one had any idea how the Feds actually managed to decrypt the hard drive they found there. Turns out, it's pretty easy to break into a hacker's computer when their password is the name of their pet cat Chewy.
In Hammond's defence, the password was technically "Chewy 123", although plopping those numbers on the end is still one of the biggest basic computer errors you can make. Which is surprising coming from the guy who managed to hack into security think-tank Stratfor's own website.