Brandon Wheat Kings
Glasgow Rangers
Toronto Blue Jays
Toronto Raptors
Toronto Maple Leafs
Winnipeg Blue Bombers, with a soft spot for the Saskatchewan Roughriders
University of Michigan Wolverines.
Grew up in New Hampshire, live in St. Louis.
MLB: Red Sox
NFL:Patriots
NHL: Bruins
NBA: Celtics (I’ll only follow if they’re actually in the playoffs; I don’t care much for basketball)
I do root for the Cardinals as my NL team, but they become my mortal enemy if they’re playing the Sox. I’m mildly interested in the Rams, but not really. I can’t bring myself to care about the Blues.
The only college team that I’ve ever really cared about consistently is UNH hockey. I’ll root for Mizzou, but I’m not invested.
NFL: Cardinals and Chargers*
MLB: Diamondbacks and Padres
NBA: Suns
NCAA: ASU Sun Devils
*NFL teams I always root against: Chiefs, Broncos and Cowboys
Grew up in northern Indiana and have lived in Tennessee for many years.
MLB: Reds (NL) White Sox (AL) Sounds (minor league)
NFL: Titans
NHL: Predators
College football in this order: Notre Dame, University of Tennessee, any team playing FSU or University of Florida, Cumberland University (Mid-South Conference)
Women’s college basketball: University of Tennessee
I’m not much of a hoops fan (they’ll probably revoke my Hoosiership for that) but I like to watch a Celtics game now and then.
MLB: Seattle Mariners
NFL: Seattle Seahawks
College Football: University of Washington
College Basketball: Gonzaga University, University of Washington
NBA: spot vacant until Seattle gets another team
Born and raised in Central New York.
MLB: Chicago White Sox
NBA: New York Knicks
NFL: San Fransisco 49ers
NHL: New Jerey Devils
Soccer/Football: Arsenal and the USA National Team
Not so new that you started watching this season or last, I take it. Otherwise, I’m simply bewildered.
Me:
NCAA Football: Miami Hurricanes
Premier League: Manchester United
MLB: Minnesota Twins
NFL: Minnesota Vikings
NBA: Minnesota Timberwolves
MLS: No strong allegiance to this point, but I’ll be a Portland Timbers fan starting this season as I plan to move to Portland in the next year.
NCAA Basketball: Minnesota Gophers
NHL: Minnesota Wild
I tend to pull for Pac10 teams, also (so long as they aren’t playing Miami).
Raised in Trenton, NJ, college in Atlanta, live in San Fran.
MLB : Giants, Phillies - No, the playoffs weren’t hard. I haven’t lived near Philly in years.
NFL : Eagles, 49ers
NBA : Suns - I have a personal connection with a very, very minor Suns player from about 20 years ago. It stuck.
NCAA FB : Georgia Tech (Alma Mater), Fresno St. (Wife’s AM)
NCAA BB : See above, Villanova
Joe
I was born in Milwaukee, and have been in North Carolina for 35 years.
NFL: Packers
NHL: Hurricanes
MLB: Cubs
NCAA: N.C. State
NFL: Cowboys
NBA: Celtics
MLB: Cubs
NHL: Hockey? Who watches hockey?
NCAA Football and all other sports except basketball: LSU
NCAA basketball: Memphis (and then LSU)
MLB: Phillies
NFL: Eagles
NBA: Sixers
NHL: Flyers
Don’t pay much attention to college sports. But, when I do.
NCAAF: I enjoy when Penn State does well. Same with Temple (A little more rarely.)
NCAAB: The Big 5: Temple, St Joe’s, Villanova, Penn, La Salle. The first two are usually my faves, the other three change depending on who is coaching at the time. When Massimino was there I rooted against V, but that’s been a while. And, I miss Speedy Morris. I like all of the ACC teams. Yes, both Duke AND UNC (somehow!) And going to the Atlantic 10, GWU.
MLB - Cubs
NFL - Bears
NHL - Blackhawks
NBA - Basketball is boring
College: Notre Dame
Interesting combination. I’d love to see your reasons for supporting each team. 
Born and raised in Michigan.
NHL: Detroit Red Wings (and as a Detroit fan, thank god for them.) 
MLB: Detroit Tigers
NFL: Detroit Lions
NBA: Detroit Pistons
I don’t really follow college sports much, but I tend to root against MSU because one of my coworkers is a well meaning but obnoxious Spartan fan so I like to give him shit when they lose. I’m also required by virtue of my Michigan residency to root against the bastard Ohio State Buckeyes anytime they do anything.
Raised in Sydney, Australia; in the US, lived in Baltimore for 8 years, and now San Diego.
NFL: Baltimore Ravens [and a home-town sympathy for the Chargers]
MLB: Baltimore Orioles [and a home-town sympathy for the Padres]
NHL: Vancouver Canucks [plus, i support any Canadian team playing a US team, and any cold-weather team against a warm-weather team]
NCAA Football: don’t really care, but anyone playing against Notre Dame or Ohio State gets my support.
EPL: nominal supporter of Liverpool, although i’m more interested in watching a good game than following a particular team.
International sports (cricket, rugby, soccer, etc.): Australia
MLB: Yankees and then a distant 2nd: Cubs
NFL: **Giants **and a distant 2nd: The Bears
NBA: I lightly root for Knicks and Nets.
NHL: No longer a fan but was a Rangers fan.
NCAA Football: Mild rooting interest in Rutgers.
NFL : Pittsburgh Steelers - I’ve also followed the Colts since I was a kid, and if the Steelers are out of the Super Bowl hunt, I’ll root for the Colts. Except last year, when I found myself rooting for the Saints for some reason.)
NHL : Pittsburgh Penguins - no second team
MLB : Pittsburgh Pirates - My favorite team and favorite sport. Since I have no hope for a playoff appearance anymore, I tend to root for an underdog in the playoffs. Last year, for example, I jumped on the Reds bandwagon at the start of the playoffs. But I have no love for the Reds or any other team.
NBA : No interest, but if forced to choose, I’d pick the Portland Trailblazers (Portland is my adopted city, so why not?) and Philadelphia 76ers (huge Dr. J fan… shows how long its been since I rooted for them)
NCAA: Pitt Panthers in all sports, but to be honest, I only really follow football and basketball.
Another one who grew up in Central Illinois. But I’ve lived in California now for 28 years.
NFL: Bear Down, Chicago Bears!
MLB: Cubs
NHL: Kings
NBA: Haven’t watched in probably 15-20 years. I used to love the Magic Johnson era Lakers.
College: Illinois
The reason that I have/had loyalties to the Kings & Lakers is because I never really followed either of those sports growing up and got into them after I moved out here. Magic was a shitload of fun to watch, but I’ve long since lost interest in NBA basketball. Hockey is a great sport to watch, but I don’t follow it closely or passionately. If I ever relocated from here, I’d probably switch loyalties to a local team in that sport. I never went to college anywhere full-time, so my college sports allegiance is based on what I grew up watching (especially Illini basketball). I would never change allegiances, but I don’t live or die with it.
But it’s Bears & Cubs until the day I die.