I tossed that idea around a bit with my salad but it didn't taste good.
The problem is that, depending on how many Anon names we have, it would be difficult, or at least problematic, to identify the Anon users to casual visitors. I don't want Anon comments to get the kind of attention that a regular user's remarks have and if the name changes it might be thought to be a real member.
Whatever we pick, I think it should be a steady name...or else an announcement made if we change it.