Sennheiser had the best table; they were giving away pens, carabiner key clips, velcro ties, stickers and mints!
They were also demonstrating the EW112-p G3 Wireless Microphone system. The party trick of the G3 is that the receiver unit has an automatic frequency scan feature that searches the available frequencies and picks the one with the least interference. The transmitter is then synced to the receiver through an infra-red connection (you have to hold the transmitter near the receiver and explicitly initiate the connection.)
An optional rechargeable battery pack, the BA 2015 accupack, can be used in place of standard AA cells, and charged while they remain inside the unit, though they cost $72.
B & H: Sennheiser EW112-p G3 Camera Mount Wireless Microphone System with ME2 Lavalier Mic (A / 516 - 558 MHz) $599.99