I saw this a while back but it turns out my uni is involved: Score, the stove that turns heat into sound into electricity. It's an intriguing project for technical reasons: turn heat into sound? Sound into electricity?
And in case you're wondering why anyone would want to turn heat into sound into electricity in real life: well it's for the developing world, where people often use stoves for cooking, and they could benefit themselves (e.g. with LED lighting) if they could harvest some of the surplus energy as electricity. Nice project.