Paying bounties for completed task is a common method in Free and Open Source Software development. The user sets a (usually monetary) bounty to fix a bug or add a feature to the program. A developer accepts the task, does the work and gets the money.
- http://bountysource.com - Open Source mediator like SourceForge but with the enhancement of a complete monetary bounty system.
- (down) Launchpad bounties - the project management software from Canonical - the commercial sponsor of Ubuntu Linux
- (down)Bounty County is a blog that lists coding bounties offered by free and open-source software projects.