Cool crypto use-case I haven't seen discussed (but maybe it has) is dominant assurance contracts for product features. This requires reliable oracles but the idea would be that users agree to pay some prize if a product develops some feature. Upon shipping the payment automatically goes through.

The hard part seems to be verification. Every product feature is more complicated than its spec so you're bound to have cases where the funders disagree whether it's actually done.

Ok, I guess this is basically repl.it bounties with a sprinkling of Gitcoin...