Are there general topics people would be interested in for hackathons that would be more interesting? I'd like to see more "hackathons for good" like http://cur

Are there general topics people would be interested in for hackathons that would be more interesting? I'd like to see more "hackathons for good" like http://cure.nyhacker.org http://cure.nyhacker.org or interesting topics like http://gamehackday.org http://gamehackday.org