After iFixit released the photoset of their Chumby One teardown, we knew the compact WiFi widget device had the potential - via circuit-board connections - for composite video output; now some enterprising modders have taken advantage of it. The mod requires soldering an RCA extender cable to the appropriate places on the mainboard, and slightly modifying the Chumby's firmware.
That mod - which is also detailed here - enables the composite-out TV encoder, which can produce both NTSC and PAL signals. Unfortunately right now only one display - either the external monitor or the Chumby One's own LCD - can be active at any one time, even though primary control is still via the 3.5-inch touchscreen.
Driving the bigger display also taxes the device's Freescale i.MX233 CPU a little more than usual, so widgets reportedly run more sluggishly. Still, if you're keen to have Pandora or any other Chumby widget on a bigger display, this is a reasonably straightforward way to do it.