As hobbes said about the stuffplug 5000 limit text.. that's a great way... Well At least it used to be... The older version of Stuffplug (don't remember what version) had a 10000 limit, if you filled conversation with 10000 smilies like
or anything... That might crash their connection and signing him off msn... Well.. At least that worked for me a couple of times..
... But this might also sign your self out beacuse of the laggy connection there is to the server when your msn has to convert : D to a
smilie... But this can be avoided if your MSN Messenger Option page and under Messages, disable the "Show Smilies".. This is a great way of hitting again on people bugging you like that!