A portable, federated, school-based social network might be an interesting end-run around the data lock-in problem. You could pitch the solution as a sort of p

A portable, federated, school-based social network might be an interesting end-run around the data lock-in problem. You could pitch the solution as a sort of portal-with-social-network-features to the school (something they're all keen to have) and you'd wind up with a huge userbase and a steady stream of profiles that want to port-out or echo-out from their school-based service each and every year. And, as even large schools are tiny on an internet-scale, scaling problems are vastly simplified. Then each outside service that wanted to be able to take these profiles in, or allow a link between an in-school profile and one of their profiles (so Sue's uploads to the photography club make it to the flickr stream their parents can subscribe to), would essentially be signing on to a common data format and interchange protocol.