I've never lined up for concert tickets.
Either the phone was used, or we used a service that involved someone lining up for you, then selling you the tickets at a premium.
Now you buy tickets on the internet. You can buy tickets by lining up or on the phone, but if it's a popular gig, you're likely to be met with "sold out" even if you're one of the first in line.
As a registered member of both major ticket sellers, I sometimes get offers to buy tickets before "the public". This usually involves entering a special code. I think I took advantage of this for the Big Day Out in 2008 and Tori Amos in 2005, but it isn't available for most gigs.
Recently in the US, LiveNation (aka ClearChannel) started selling tickets to concerts. Their first effort was to release the tickets for the reforming of Phish all on the same day. Their website crashed [RollingStone.com]. Ticketmaster also had the same problem with Bruce Springsteen's tour.
Too many people want tickets for too many shows at once. The website can't deal with it.
Allowing some people to pre-buy tickets helps, but disadvantages fans who don't want to be members of a ticket selling company.
One obvious answer is to sell each show, or groups of shows physically distant from each other, on different days.
Another is perhaps more fan friendly, and provides some pre-gig information that should be helpful for deciding venue sizes...
This should prevent most of the problems with 100,000 people trying to hit a website at once... but only really works for General Admission gigs.
Any gig requiring seating has the ultimate problem of first-in-best-seats. I don't quite know how to solve that, except via some kind of lottery.
Ideas?
It also disadvantages very popular bands who only want to do a few small gigs. Pre-registrations could force what was to be a small tour into a huge undertaking. Perhaps pre-registrations could be capped with a certain amount being guaranteed a ticket... although that leads to obvious problems...
Fans could also pre-register for unannounced gigs. There are a number of bands I would attend if they announced a tour. Such a register would gig bands an idea of whether a tour is worth it.