@Cobrabrr: just to clarify, I wasn't suggesting actually doing the illegal stuff. That's what botnets do. They use a large workforce, too - they just don't pay their workers as well...

Anyway, I think Bitcoin as a whole would profit a lot - people with money and a desire to do some large-scale computation work would bring a whole new dimension into the business. It'll be interesting to see if there is a "killer application" for this kind of business.

One application (besides the ones I listed already) could be, ironically, Bitcoin mining: relatively low bandwidth requirements, relatively high computing requirements and a relatively clear incentive: Want your own block (to include some exotic kind of transaction, maybe)? Buy it!