PGP (Pretty Good Privacy) is a cryptographic algorithm that is used to assure your data won't be readable from others. Although the concept doesn't belong to MIT, there was the actual place it became a reality. In the past i think it was illegal to use PGP outside the states because NSA considered it technology that must stay inside the borders of usa. Now there isn't any such limitation. Hm.
www.pgp.com seems to be a product that uses the technology. I haven't seen it before