Codemash - probably the single best regional development conference in the country - sold out of 1200 tickets in 20 minutes. This is pretty impressive, but hardly unheard of. ShmooCon, the DC security conference, sells out in a few seconds every year. and has gone to a lottery system to distribute tickets. This is not optimal because many who want to go and should go are not admitted by pure bad luck, making the conference worse overall. While degradation in quality is an effective way to reduce queue length, it isn't one that anyone really wants.
I am fascinated with the economics and psychology behind popular events and their queues. Generally, for something like a concert, you will drive the queue length down with cost. You want to see Madonna? Fine - $350. Too rich for your blood? Good - we had too many people anyway. This works for a lot of entertainment topics, actually, since there is no moral standard for admittance.
Colleges are another story. A good college will have an abundance of admissions, but only a few will be accepted. Private schools will filter with cost as well - but is this a good idea? Do you want those with the most money, or those who have the best chance for success? Those two items won't always overlap. The Objectivist seminar that used to be in Virginia every year had a good solution: they filtered with high cost but had a scholarship program. To apply for a scholarship, you needed to do a LOT of writing, and it had to be GOOD. Few went to the trouble, but those who did REALLY wanted to be there. I know, because I was a recipient in 1997.
But how to reduce the queue for something like Codemash? Eventually something like a lottery will have to be instituted, because next year noone trying to register more than a few people at a time will be able to get tickets. But see, that is a problem, as this is a conference where people who really WANT to be there, should be there. High prices have a similar problem - in general the community is not short on funds so that will probably do nothing except tick people off. (Although a charity could get involved which would be neat). Even then, do we really want to put the con out of the reach of students? Early registration - effectively reserving space WAY in advance - is another possible solution. I am sure there are other options - guess I need to get out the queuing textbook from OSU.