Feel free to add your own leagues that I don't follow. Here's mine:
MLB
Favorite: Cincinnati Reds
Least favorite: Chicago Cubs; St. Louis Cardinals
NFL
Favorite: Cincinnati Bengals
Least favorite: Pittsburgh Steelers
NHL
Favorite: Colorado Avalanche
Least favorite: Detroit Red Wings; Vancouver Canucks; Minnesota Wild
NCAA football
Favorite: Ohio State Buckeyes; Cincinnati Bearcats
Least favorite: Michigan Wolverines; LSU Tigers
NCAA basketball
Favorite: Dayton Flyers; Ohio State Buckeyes; Cincinnati Bearcats
Least favorite: Xavier Musketeers; Indiana Hoosiers; Louisville Cardinals