I think a social sharing protocol could be better than a device. A protocol that lets you decide what to share and with who. A protocol that lets you decide where you store your data, be it your local storage, webspace or cloud storage, share your personal text messages, pictures and videos, search for shared content through the protocol. Making a device and hanging to that will make it just another means of selling hardware with an incentive. Open up the web again and let people share. A bit like wordpress does, making blogging available to the masses, be it on the .com community or your own hosting. If those things can be tied together in a single protocol that would be nice, a truly decentralised social network, just like your basic rss feed and readers but on steroids. Plug that on kickstarter and I am in!
We probably can apply the concept of the open ledger of cryptocurrency to our social network. Social coins holders could secure the blockchain and the privacy.