One interesting feature of MashupCamp is "SpeedGeeking". It works like this:

• anyone with a (mashup) demo makes an announcement in the morning they're going to be speedgeeking and writes a brief description of what they're doing on the board
  
• every demoer gets their own table to setup
  
• small groups of people go to each table to see your demo
• you get 5 minutes for a demo; when 5 minutes is up the horn goes off
  and each groups move on to new table
• every person gets a wooden nickle which they give to their favorite demo
• prizes for best demos and runner-ups, provided by generous companies
  

In MashupCamp3, the particular format was:

• two days of demos, 90 minutes allocated to each
• there were 28 demos; unforunately we didn't get to see many of them since we were demoing ourselves
  

Here's my notes about how to do this effectively:

• one person talking and one person driving is _definitely_ the way to go; I strongly suspect this goes for DemoCamp too! It's hard to engage your audience and engage your computer at the same time, especially things may go off on a tagent or something may break
• you need power to run your computer; we ran out of power an hour in on Day 1. Insist on a seat near a wall if need be; Hotel@MIT is a great geek hotel (wireless and gadgets everywhere) but there's a definitely lack of power outlets there. They've actually got back to me on this point saying they're planning to address this issue.
• less is more. On Day 1 we demonstrated cross posting events to Google Calendar, Google Base, Upcoming plus socially linking the event to Del.icio.us. Response was polite. On Day 2 we retooled to show how, using structured blogging, to sell a car on Google Base from within your blog. The message was the same (centrally control your data, push to where you want to see it) but on the second day we had people staying past the 5 minute limit to hear more about how we did it.
• have lots of water on hand; we did around 25 demos and it's pretty tiring.
  

We ended up a copy of MS Developer Works for the effort, which was mostly worth the blown out vocal chords :-)

There's a picture of Tim and I (with the thumb) demoing here.