What to do with multiple OpenIDs?

The ability to have a single online identity is a worthwhile goal, in my opinion, and OpenID seems to be a major step in that direction. It allows login to any OpenID-enabled website through the use of your single identity, and tools like Verisign's Seatbelt make that even simpler. I'm quite pleased to see that more and more websites are adopting OpenID as a means of signing up or signing in.

The question I have now is: What do I do with multiple OpenID accounts?

Since more websites are using OpenID, more of them are also making their existing users able to use their existing logins as OpenIDs. This means that I already have at least 3 OpenIDs and no way to consolidate them.

This might seem like it has an easy solution - simply stop using two of them. The problem is that the one I've been using most already isn't the Google one, since Google's change to OpenID is more recent - and starting a new account on Google with my favoured OpenID would require too many transfers of data and notifications of third parties to be worth it.

So basically, I am looking for a way to use one of my OpenIDs to absorb the existing permissions and accounts of the others.