Toontown Online, one of the largest Family orientated online game worlds is now available for all you Macintosh owners.
Here is the blurb from the official Toontown Site:
"Calling all Toons! The best game in the entire Tooniverse is now available on Macintosh computers! Spread the word and get your Macintosh friends playing Toontown today."
Just visit the official site and sign up, there is a free trial for 3 days, but that should get you hooked.