The furre tracking thing might not work, but I had another idea that's similar but likewise quite different. I think it'd be cool if it were possible for individual people to flag themselves as IC! All it'd do is add them to a list you can bring up by saying !peopleic or something. Flagging yourself means walk-up RP is wanted and desired, and that all of your actions, be they posed or performed with your avatar, are currently all IC--sitting in a bar, walking around town, hanging at the docks, etc. (Entering the OOC room, either manually or due to idling, automatically turns your flag off, of course.)
Being flagged IC also means you might be posting to yourself (and/or controlling NPCs), doing what your character would be doing at the Time/place. This makes walk-ups especially fun.
If you walk around a bit and happen to come across one of the people on the list, you know you're free to strike up some roleplay with them!
I think this'd really encourage the kind of RP we're going for here and would make accidental meetings a lot more common. If two people with their IC flags up are wandering around, they more or less have to interact somehow, even if it's just to wave as they walk by, or pose the way their character ignores the other's presence.
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