A lot of people have posted here about alternatives that retain privacy, then others lament "who would do it? ... could a start-up succeed?"
There is an alternative -- on the horizon, anyway -- that's all about privacy. You don't have to choose between privacy from your community and privacy from a faceless corporation.
The FreedomBox project -- http://www.freedomboxfoundation.org, inspired by Eben Moglen, who helped write the GPL -- aims to create a network where users own their own data. If you've used, say, Wikipedia or a site run on Linux, you know how projects based on his vision can work in time.
It's not ready here and now, but this community can help contribute to it.
One component to FreedomBox is to replace many current "cloud-based" services which gather and store personal data with peer-to-peer versions where you own your data on your FreedomBox.