Wow, that's a really great idea. I like how it doesn't require any extra software and basically creates a real bounty system.
I am thinking this could be used anywhere. Even in internal ticket systems, or issues on a github repository. The important thing is that it is judged by the person who does the paying. No fancy voting system needed.
I was thinking of building a bounty system for all sorts of things where people all put money into an address and when someone does something to achieve that bounty it gets paid out. The verification part just seemed like it would get too complicated and too subject to gaming/hacking.
An adhoc system can just be layered on top of all current systems, and human judgement is the protection against hackers.