On the topic of scalpers, Louis CK apparently hired  scalpers to help build some anti-scalper checks (I assume it is similar to fraud detection rules: multiple purchases from the same IP, out of town billing addresses) that runs on his website where he now sells all of his tickets. If you get flagged by a rule, the ticket goes to will-call, so you have to show ID and the credit card at the event. That small step to prevent it significantly reduces the resale value for a scalper who can't attend the event.
Here's the interesting part: It worked! Roughly 25% of all tickets for major shows fall into the hands of scalpers. On Louis CK's last tour, of all 125k+ tickets he sold, than than 1% were scalped. 
What's really terrible about the whole scalping business is that it would be solved, but only by the people who care least: The venue has a perverse incentive allowing scalpers to buy every last ticket they can get their greedy little hands on. As long as a ticket gets sold, they don't care. Screw the fans.
Possibly NSFW language in these links.
Everything I've seen trying to explain the scalping phenomenon appeals to the idea that this is completely backwards from true. Specifically, the theory is that the venue's incentive is to fill seats, which is why tickets are so dramatically underpriced (price too low -> shortage of seats -> all seats get filled -> the act appears to be popular). From the venue's perspective, a seat sold to a scalper is a seat they lose money on and that might not be filled during the performance (since the scalper's incentive is to charge a realistic price), which is a double loss to the venue.
In sum, selling tickets to scalpers gets the venues an amount of money they don't want (they were guaranteed to sell out anyway), in order to generate an effect they don't want (some seats will be empty during the performance). Where's the perverse incentive?