For many years, Capture the Flag with Stuff reigned as the supreme overelaborated fantasy-themed sport played by overenergetic college students. Or, well, probably not. I have no idea what the kids get up to these days, really. I didn't know what kids got up to in those days. But CtFwS was the one I was aware of -- mostly because I started it. (It has evolved considerably since then; see the new KGB rules used at CMU.)
(Moopsball was the supreme overelaborated fantasy-themed sport not played by enthusiastic college students. Sadly, it is no longer not played because it's too much work; it is now not played because nobody remembers it. Sic transit the guy with the hula hoop.)
But the new generation has arrived, and that means Quidditch. As in, the kids who struggled through Philosopher's Stone at age 8 are now in college. Quidditch is what they want, and they have made it work.
(Here I tried to interpolate some joke about what the devoted fans of Twilight will be playing at college in five-ish years. My first idea was too creepy to put in writing and they went downhill from there. Make up your own, I'll be hiding under this extremely sparkly rock.)
If you've read the Harry Potter books, you know how Quidditch works. If not, this blog post will do nothing for you... okay, look, hit Wikipedia and come back. Or don't come back, because that entry has a summary of Muggle Quidditch, so what do you need me for? Huh? I'll just go hide under that extremely sparkly rock over there.
(PS: Wikipedia keeps its Quidditch page up to date, but they delete the page explaining Kosho? 1000% lame.) (EDIT-ADD: Thank you Deletionpedia.)
Muggle Quidditch! Rule one: you must run around holding a broomstick between your legs. ("Harder than it looks, and just as awkward," says one player.) Rule two: throw the Quaffle (a volleyball) through the goal hoop. Rule three: you must drop the Quaffle if someone clobbers you with a Bludger (dodgeball). Rule four: the game ends when someone grabs the Golden Snitch. The Golden Snitch is played by a very fast person, dressed in gold, with a tennis ball tied around his or her waist. There are other rules but they don't seem to prevent shoving and tackling, so that's basically what the game winds up being about.
So it's simultaneous tackle rugby, tag, and dodgeball, all being played on the same field among different subsets of the players. I know it sounds like I'm making fun of this; but I'm impressed. All the players have to have a clear idea of what's going on, to make this work.
I also admire that it's not just a game -- it's an event. The 2008 World Cup at Middlebury College had costumes, characters, role-playing. (See, there's a reason I brought up Moopsball.) There are extravagant team names. There are people on stilts. The league commissioner wears a top hat. Everything is better when top hats are involved.
The biggest difference between this and Rowling's fictional Quidditch -- well, is that the players can't fly. (Everyone agrees that it's a really, really muddy time for all. On the positive side, if you slip, it's not 150 feet to the ground.)
The biggest chosen difference is that grabbing the Golden Snitch is worth only 30 points, or three times the value of a goal -- not fifteen times, as Rowling had it. This brings the game into something like balance. Both Seekers have to keep an eye on the score as well as the Snitch. Unless the score is very close, one Seeker will be actively running interference against the other, rather than trying to catch the Snitch herself.
Here's an article about the 2008 World Cup. There's also a rudimentary IQA web site. See also, a documentary produced by Justin Bogart (youtube video).