At http://openid.org/ we're releasing a new feature to allow you to copy and paste data privately between ANY of the 350 Million+ OpenID's - that is, the sender and recepient(s) don't even need to have an OpenID.ORG account - any OpenID account will do.
And there's more - we provide the same functionality for mobile devices too (we need your feedback on that one btw!).
The home of the Copy & Paste application is here.
The mobile home is here.
What this means is you can copy some data and specify the exact OpenID's who can read that data - you can copy from a mobile device and they can read in a browser or another mobile device. Complete freedom.
Also, web and mobile developers can make it easy for people to copy and paste data between OpenID's by using the (fairly simple) API which can be found here. This works for web and mobile devices.
We do of course hope you sign up for an OpenID at http://openid.org/ but the authentication for Copy and Paste is completely distributed so all your friends can join in.