While it wasn't operational, the Wireless Racing Wheel was touchable (unlike at E3, where it was shown for the first time). The pedals impressed us - while most "walk away" from you when you slam on the gas or brakes, the 360 version features a little lip where you tuck in your heels. Essentially, you keep the pedals from moving. It felt comfortable when we tried it, but we didn't race with it.
Same goes for the Wireless Headset, a peripheral a lot of gamers have been eager to see. It's reported to be higher fidelity, louder, and all-around a major improvement over the wired headset. Because the Xbox 360 can recognize a whopping 40 different wireless channels, four players using wireless controllers and wireless headsets won't even tax the system. A soft rubber ring wraps around your ear, and a padded speaker sits directly over your ear canal, while the reverse side features volume buttons.
The external HD-DVD drive was shown too, though it's not yet operational. Our friends from Microsoft reiterated that the drive would not be used for gaming - it's purely a movie machine, so you don't have to worry about being "forced" to buy more hardware to play Halo 3 or anything silly like that. A USB cable sends the encrypted/compressed data from the movie disc to the 360, and the 360 itself is where it gets decompressed and converted into luscious video and surround-sound audio. The drive requires external power, but there's two more USB ports on the drive for your trouble.