Oh yes!
For those who have the Wii and the DS, later this year, a Sonic the Hedgehog/Mario team-up game is coming out.
Mario, Sonic qualify for Wii, DS Olympics
Famous Sega and Nintendo characters will star together in Olympic Games-themed sports title on Nintendo platforms later this year.
By Emma Boyes, GameSpot UK
Posted Mar 28, 2007 3:26 am PT
Two of video games' most recognisable icons will soon be competing against each other. Sega and Nintendo have announced a new title, Mario & Sonic at the Olympic Games, which will be released on the Nintendo Wii and DS. This will be the first time that the two well-known digital stars have appeared in a game together.
Other characters that gamers will be able to play as or against include Luigi, Knuckles, Yoshi, and Tails. The environments in the game will be based on the venues at the Beijing 2008 Olympic Games, and events include table tennis, 100 metres running, and swimming.
http://www.gamespot.com/wii/sports/mariosonicattheolympicgames/news.html?sid=6168192&mode=recent