This is actually provided functionality in EPiServer Relate+.
They use dotnetopenauth and deliver a custom role provider where they save profile information. Its probably worth considering just purchasing relate vs building/maintaining the functionality yourself. (Relate actually delivers a lot of extra intranet functionality out of the box)
If you're set on building it internal, this asp.net video/article may give you a decent start.
We are developing an intranet for my company. We have been investigating the possability of using openID for the login. However we want the possability for the users to have there own profile page on wich they have the right to edit.
We are using the dotnetopenauth library wich handles the openID protocol.
For this yo work we need to use a custom role provider or something that can be linked to openID and a user for each openID user.
Any ideas on how this can be done? Or is it possible?