Auctioning off your event?

Here's an interesting idea from Seth Godin: Run an auction for events with limited seating. Inspired by this new Google Documents feature, Godin says,

Say you want 200 people to come to a networking event, the sort of thing that's no fun if only a dozen or two show up... Instead of charging $50 a ticket, why not charge $1 for the first five tickets, $2 for the next five, and on to $500 for the last ten? You'll earn just as much (if not more) but reward the brave who sign up early. (The folks who like to wait until the last minute 'to be sure' end up paying for the privilege). It's easy to imagine a simple interface to set up whatever graduated pricing model you'd like...

Why don't airlines have tools in place to make it easy to integrate charter flights with conventions so flights run when (and where) people are going? Flights for passengers instead of passengers for flights...

He winds up by saying, "I guess my point is that this is just the beginning of using internet tools to change the world we interact with, as opposed to trying to make it easy to interact with the standard world using the Internet." Which really struck me, having tried to put exactly this thought into words over at this post on Acronym about Web 2.0.