The administrator may have enabled RSS syndication, this allows you to view newly created threads in guest viewable forums without visiting the board.
The feeds are currently provided in two formats, RSS and RSS v2. The differences are as follows:
To add this to MyYahoo click here.
The forums to which this applies can also be limited to specific guest viewable forums by adding another parameter to the URL containing the forumids as follows:
If you would like the content to be generated for multiple forums you can separate the forumids by commas.