custom emoticons are stored in C:/Documents And Settings/<windows username>/Application Data/Microsoft/MSN Messenger/<your passport number>custom emoticons
there the emoticons are named randomly and end in .dat, copy the files somewhere else and rename to .gif
notes: <windows username> is your windows username you use to log in
<passport number> is obviously the number of your passport. there is a program out there that can tell you what the number is for your account or you can just check each folder
Stuffplug can save the custom emoticons of anyone who had sent you recently, they don't nececeraly have to be ripped
(whew, too so long to type. rarely are my posts so descriptive)