shifting the topic back to tablets a bit, what are all the connectivity options for hooking tablets to things?
For iPad:
Apple TV gives me wireless connection to my big TV
there's cables for VGA, component, hdmi at varying prices
a USB port (the camera adapter) that also does MIDI if your keyboard has a USB jack
Alesis has a full dock (marketed for garageband users) with midi, usb, XLR, 1/4", 1/8" and VGA jack
there's a few other MIDI adapters, and headphone jack adapters for guitars
I saw an GeekSquad commercial that happened to show an iPad doing AirPlay to a mini projector (I assumed thats what I was seeing).
are there any other doodads? And what can the non-iOS tablets be hooked up to?