Everyone has seen the analog-stick nunchuck, but it won't be the only attachment for the Wiimote. Nintendo hasn't finalized designs yet, but I managed to get a look at a near-final version of the classic gamepad attachment for the Wiimote, along with a clip-on Wiimote gun handle.
The Wiimote will have a conventional gamepad attachment for use with the classics-playing Virtual Console. The gamepad sports at least six buttons, a classic directional pad, and two analog sticks. It looks fairly flat and lackluster, but it fits in well with the Wii's minimalistic design.
I also noticed a gun handle attachment to the Wiimote. Rather than attach via cord for a nunchuck configuration, the gun attachment fits directly around the Wiimote, turning the controller into a gun barrel. Nintendo hasn't confirmed that the guntroller attachment will actually be released, however; the model shown at its booth was just a mock-up.