The Office Labs team has built a cool game to help learn the ribbon user interface in Word, Excel, and Powerpoint 2007, and the upcoming Office 2010.
Check it out here
http://www.officelabs.com/ribbonhero
http://www.officelabs.com/Lists/Posts/Post.aspx?ID=88
and on Facebook
http://apps.facebook.com/ribbonhero/
ZDNet
http://blogs.zdnet.com/BTL/?p=29685&tag=col1;post-3558