I am considering (not doing yet, just considering) turning my OpenID reading lists into the equivalent of my old filters. You can make an essentially arbritary number of validated OpenIDs with a little creativity, and have a separate reading list for each.

(This got somewhat less urgent when I realized there was a built-in users vs communities filter. Mind you, I found it via the links on the profile page; I hadn't noticed the dropdown on the navbar until I read this post, sigh.)