I like the idea of OpenID, I really do. But few of my target users have even heard of it - yet. If I want to offer OpenID as an option, my only choice would seem to come down to offering BOTH email/password authentication AND OpenID.
I've seen several sites that use this combination and the idea seems unappealing to put it mildly. Placing both options on the same screen is distracting and pointless if only 10% of users will even care about OpenID.
So I'm wondering, how could I offer a single user interface that supports BOTH OpenID and email/password for authentication and account creation?
One possibility I've been considering is to use a single OpenID/email field that can detect whether an email or OpenID was used and then dynamically adjust the interface accordingly.
For example, an account creation page might start off with a single field labelled "email" with some unobtrusive text along the lines of "we support OpenID". If a user enters a url, then the interface switches to an OpenID account creation page (via JavaScript). If an email address is entered, nothing happens.
What's the best method you've seen for hiding OpenID from the average user, but at the same time letting tech-savvy users know that your site supports it?