This is a silly AppleScript script that lets you quickly replace your iChat picture with the current picture of anyone in your Buddy List. This makes for some interesting chats, as your Buddy will suddenly appear to be talking to him/herself! (Note, though, that the selected Buddy doen't have to be online for the larceny to occur.)
tell application "iChat"
set stealFromWho to name of every account
set stealFromChoice to (choose from list stealFromWho with prompt ¬
"Steal iChat Picture of:") as string
set picToSteal to image of account stealFromChoice
end tell
If you don't want to have to manually restore your own picture (the fun gets annoying after a bit), just insert the following snippet of code before the end tell:
set oldImage to image
set image to picToSteal
delay 10
set image to oldImage
Vary the value of the delay command to suit your purposes.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20050322214419259