Data Dictionary Creator was recently released by Jon Galloway. It's a UI allowing you to document your SQL Server databases by storing the documentation in extended properties, and then exporting it as Excel, XML, etc. The nice thing is it stores the documentation in the same place that SQL Server normally stores its descriptions.

So instead of using the SQL Server tools to update your descriptions like this (ugh):

You can now use a cool lil' UI to do it, like this!