No not really but convo notifier and convo close sometimes work like that. Heres the links:
http://www.msgpluslive.net/scripts/view/115-Convo-Notifier/
http://shoutbox.menthix.net/showthread.php?tid=64418&page=1
I like the second one.
Features:
* Displays a toast message when someone starts a conversation with you.
* Displays a toast message when someone adds you to his/her contact list.
* Displays a toast message when someone removes you from his/her contact list.
* When you already have a conversation window opened with the remote user, you won't get a toast message.
* When you click the toast, a conversation window with the remote user will be opened. POSTED FROM THE THREAD
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