check out this link for some info about them:
http://www.mess.be/msnmessengerfaq/idx/0/102/arti...play_Pictures.html
Edit: here is a quote from mess.be news:
"Zero1 says:
Well, after only four days since finding the first example of dynamic display pictures from Blue Mountain, or Muggins as they are now called, we have finally been able to get a working example inside MSN Messenger.
The internal release of MSN Messenger 7.0.0732 (which later got leaked onto the internet late last night) was found to be Muggins capable. However, any of your contacts who have an older version of MSN Messenger (even an older 7.0 beta) will only see a static image of the top half of the muggin.
On the other hand, if you and your contact both have the new MSN Messenger beta you will be able to view each others muggins, change your muggin's mood by what emoticons you use, change your muggin's mood from a menu, not to mention view somebodys Muggin in their contact card."
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