What will the sports we love look like in 2050?
Manchester United fans might say that the future of football has already arrived - and he's called Wayne Rooney.
But enough of such petty banter. We're talking here about big ideas and crazy concepts - what over-paid management gurus would call blue-sky thinking.
We've come up with a few propositions, mocked up some images and then asked the experts how likely those things are to happen.
If you have any notions of your own, email them to us using the form on the right. The more innovative, the better...
CRICKET ON THE EDGE
The use of the third umpire to adjudicate on run-outs and stumpings is now an accepted part of the game.
But why not extend the range of decisions that technology can clarify?
Not sure whether a batsman has nicked a delivery to the wicketkeeper? A sensor built into the edge of the bat could send an instant signal to the umpire's ear-piece if it makes contact with the ball.
Just think - no more contentious (or incorrect) decisions, no more sly appeals from behind the stumps and no more stomping back to the pavilion by disconsolate batsmen.
Is it possible? Steve Carter of Hawk-Eye, the company behind Channel 4's ball-tracking, lbw-deciding graphics, has no doubt.
"There is already a tape developed that can be wrapped round the bat in a very thin layer to give you such a signal when it meets the ball, " he says.
"The problem is that it changes the way the ball comes off the bat. And international batsmen aren't keen to try it, probably because they don't want to be given out."
TENNIS COURTS SUCCESS
Cyclops is all very well for helping line judges decide whether a serve is in or not.
But it cannot be used once a rally is in progress. And hey - why not get rid of line judges altogether?
They don't always get it right, they cost money to employ and those blazers and slacks are so last century.
By underlaying the entire court with sensors and using balls in-laid with a special conductive material, it would be possible to judge with complete accuracy whether a shot was in or out.
If it's out, a loud noise signals the fact to players, umpire and spectators.
You saw chalk dust, Mr McEnroe? Who cares?
The game's rule-makers do, that's who.
"We can't see it happening in the near future," said a spokesman for the Lawn Tennis Association.
"We would be talking about hundreds of courts and thousands of balls - and that would be a massive expense."
Ian Pearson, a futurologist with BT, foresees other problems.
"A tennis ball is hit at 100mph, and it is deforming elastically all the way through its flight, going from round to rugby ball-shaped and back again.
"So a sensor would not be able to give an exact indication of where the ball was."
Then again, changes are already in motion.
Players at the Superset tournament will be allowed to appeal to the umpire if they genuinely believe a line call is incorrect - and the umpire will use Hawk-Eye technology to examine the point.
"We can be accurate to within three millimetres," says Steve Carter. "As soon as the rally is finished, you can watch it again in real-time on Hawk-Eye."
Improvements in positioning systems in the next few years should also allow television viewers to enjoy instant interactive replays.
"You could pretend you were the ball, and see what it was like to be whacked through the air at 100mph," says Pearson.
ATHLETICS JUMPS INTO THE FUTURE
The long jump is all very well. But the plasticine marker used to judge fouls on the take-off board has got to go.
And why should athletes jump from one small area, anyway? Surely the event should be a test of who can jump the furthest, not who can jump the furthest from one particular point.
A chip in the athlete's spikes could be used to give a perfect indication of take-off point from the runway
And replacing the out-moded sand pit would be an impact gel which retains the shape of the jumper for a few moments to allow measurement before morphing back to its original shape for the next jump.
Could it happen? Maybe.
"We are always looking at new ideas and technologies to evolve sports and make them more exciting or accessible," says Steve Chisholm of Fast Track, the company that organises the big athletics meets in the UK.
"One idea which has been considered for the sprint events, and which could happen immediately, would be to make the winner's lane light-up when they cross the line.
"Given the narrow margins of victory in the sprints, often spectators are unaware of who has crossed the line first.
"With this new initiative, a sensor linked to the photo-finish equipment would trigger immediately as the winner crossed the line. This would lead to a golden spotlight identifying the winners lane."
What else? Javelins could to be fitted with light pulses to make them easier to view as they fly through the air - or be modified so that they leave a laser-imprint in the air, highlighting their arched trajectory from point of release to the point of impact.
"These could be colour-coded to represent different athletes and would be an interesting visual way to compare performances," says Chisholm.
MOTO GP GETS SAFE
Cars have air-bags to protect drivers in the event of a crash. Moto GP riders often come off their bikes and injure themselves.
Put them together and what do you have? The personal airbag-suit.
Okay, so the name's not too catchy, but the concept is good. When a rider is thrown from their bike, their suit instantly inflates and cushions their impact on the tarmac.
It's an idea so good that it's almost happening already.
"A company called Dainese make a jacket called the D-Air, which might be out in 2006," says Daniel Thornton, products editor of Motorcycle News.
"It's made of three separate air-bags that inflate in 30 milliseconds - but a lot of people have questions about what happens if it inflates at the wrong time.
"Professional riders do also not want to be riding in anything too bulky or non-aerodynamic."
Pearson fears that such an air-bag would actually make motorbikes less safe - because riders would think they could take more risks.
"They've always said that the way to improve safety in cars is not to keep making improvements in in-car protection, but to put a six-inch nail in the middle of the steering-wheel and dispense with seat-belts," he says.
"That way, people would drive astonishingly carefully, because they would know that if they crashed, they would be killed."
What do you think sport will look like in 50 years' time?
Send your ideas to us using the post-form on the top right of this story - or you can e-mail scans of paintings, drawings or sketches to firstname.lastname@example.org
Or e-mail us one you've done in Microsoft Paint or a similar graphics application. Send attachments preferably as .jpg files, no larger than 1Mb.