I finally had time to read the 2 DevCon articles sent by Roxanne and Marc. If you haven't read them yet, this is a must as they are a good resume of what DevCon is.
On a funny part, on Marc's article, you will see a mention about "We had many creative (or brain dead) people who started up regular speed waves, slow motion (VB) waves and super slow motion (VJ) waves.". Guess who started those waves? :) Also, as you may have seen, I had better success in starting those waves with 1300 people than the one I tried in the restaurant the next day. :)