Ask HN: Crowdfunding for GitHub Issues?

I'm looking for something a bit like Kickstarter for specific GitHub issues. Imagine someone creates an issue for "Add feature X". A developer reviews it and determines that she can solve it with $1,000 funding, so she writes a "deliverable summary" in the issue defining her solution proposal, so users can know what they're funding. 100 people want the feature, and on average they pledge $10. The goal is met, so the developer begins work. Once completed, she may claim the funding, and everyone's cards are charged (or funding accounts are debited.) Commission for this service is then taken, and the net amount is sent to her bank account.

Does anything like this exist, even in general without being attached to GitHub issues?