This little Samsung attachment will let your Galaxy Tab 10.1 take advantage of Honeycomb's USB host mode, which lets you connect game controllers and cameras and extend the functionality of the touchscreen device.
One end plugs into the 30-pin dock connector on the bottom of the Galaxy Tab 10.1 and the other end has a female socket for a standard USB connector. Mice, keyboards, flash drives... they'll all work. $US20. [Samsung via Engadget via Gadget Lab]