I would suggest offering a flash for the hot-shoe mount on advanced digital cameras. I have only seen flashes at the $100+ range for DSLR units. Something in the $50 range for the point and shoot class of digital cameras could be very useful.
Not using the built in flash doubles battery life, the flash will have it's own batteries.
External flash unit can provide options like tilt, difussion and extended range.
External flash unit need not be as large as one for DSLR.
