Yahoo! web messenger
The Yahoo! web messenger web part shows Yahoo! Messenger Pingbox, which allows users to communicate with you via Yahoo! Messenger. Adobe Flash Player 9.0 or higher is required in the client browser for the web part to be displayed.
For the web part to work, you need to create a Pingbox on the following address: http://messenger.yahoo.com/pingbox/studio
You need a Yahoo! account to access the page. Once you have the Pingbox created, you need to search the generated HTML code for the "flashvars" parameter and copy its whole value (including the "wid=" part) into the Messenger ID property of the web part.