I can't wait the moment Chumby will be available at the store, as it seems extremely promising. I am providing here some suggestions both software and hardware, the latter could be tremendous improvements for the device.

Actually if Chumby is supposed to sit, amongst other things, on my bedside, than I would definitely like it to switch off its lcd screen backlight when it's dark. It would be a matter of using an analog IO pin, if available, and a cheap photoresistor.
A rechargeable battery would be a tremendous asset, although I imagine both the screen and the wifi transceiver are demanding in terms of power.

Softwarewise consider that if I can use Chumby as an alarm, than with a realplayer or VLC modified client I could have a wifi radio alarm clock.
A skype client i definitely a must, since the device is fitted with a microphone.
An MRTG applet would make Chumby sitting on almost every IT specialist's desk.

I don't understand fully the advantage of having a 3 axis accelerometer, but then a very simple seismograph widget should be easy to develop.

Best regards to all.
LPP