Buttons, badges that are different colors, or find a sponsor to give t-shirts to the technical people for each day of the show? The propeller beanie isn't really something I picture many of us wearing (well ... until it advances to the point we can use it as a personal transportation device), but anything to differentiate the real techies is good.

I should also point out that meaningful conversations can happen between the marketeer and techies, but what do we do with the non-exibitor PHBs that attend.