Just the fixed list of avatars for now. For some reason, the software has been really persnickety about allowing the uploading of avatars (in other words, it don't work, for reasons which appear to have stumped some experts I asked about it). So you're stuck with what we've got -- apologies!
(If there's something Jim-related out there that seems to be missing, I'm happy to add in new avatars, just let me know.)
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