Not really a startup per se as it's a non-profit hobby project, but still relevant I suppose since it is, after all, a tech-powered platform. 2studentbodies is a dating website targeted toward college campuses/students.

It's a mashup of Craigslist (ad-style posts), IRC (group-based chat with private messaging), and the now-defunct LikeALittle (college-oriented subsites with the ability to flirt anonymously.)