Note the five wireless cards and antennas on the computer, they are sitting in the chill out room capturing all the wireless traffic on the net at Defcon, and I mean ALL the wireless traffic. While they are one of the good guys, they are not alone in having rigs like this, and not all of those are good guys. Laptop stays in bag, wireless off thank you very much.
You get others, like Digital Revelation with the same type of rig set up, but they are hard at work on the 'Capture the Flag' hacking contest. These groups are quite serious, to the point of usually getting annoyed if you want to chat, they are dug in to the contest hard. If you ever want to secure your network, and think you can get by while cutting a few corners, there are people like this out there, and not all of them have your best interests at heart.
Walking around Defcon 13, you get a clear sense of what the terms 'this is what you are up against' and 'they are better than you' mean. These are the light, happy and quite friendly guys who are on your side. The darker, less happy and not as friendly guys are roaming the show too, and hopefully we will be able to bring you more about what happens when the two sides meet. Stay tuned. µ