There are a range of ways that cloud computing can be used to leverage the power of a range of machine to achieve cheaply what you wouldn’t necessarily invest physically in. And to crack PGP or system passwords, you typically just need a lot of machines. So there are a few demonstrations here and here that show off the whole process, including spawning more instances than they typicially want you to 🙂 It’s all based on using ElcomSoft’s Distributed Password Recovery.
Cool! 🙂