The the problem with internal hubs is removing the rear wheel when changing a tire.

How hard would it be to rig up some primitive rf gear transmission? perhaps with solar cells to prevent dead batteries?

Imo not that much of a problem with internal hubs. Basically the same as removing the rear wheel on a single speed, fixed gear or coaster brake hub bike. The Rohloff gear hub is even available with a quick release axle. The only additional step compared to a SS/FG is detaching and reattaching the shifter cable. A little practice before having a flat is recommended. A coaster brake hub is a bigger pain due to the need to disconnect and reconnect the torque arm.

Not sure what you mean by rf gear transmission.

Solar cells with enough capacity to run a electric bike, or keep a electric bicycle battery charged, would require too large an area of solar cells to be practical to mount on a bike. Expensive too.

rf = Radio Frequency. Basically he wants to run a wireless, bluetooth-like link between the shifter and the internally geared hub to get away from the hassle of disconnecting the shifter cable when pulling the rear wheel.

The solar cells were probably only to meant to power the electric, RF-controlled shifter and not the actual propulsion of the bike. There's a decent chance that it could work.

Better to use a flat resistant rear tube.
Removing the back wheel isn't so hard that one needs to go to such heroic measures. It would be prohibitively expensive and finicky.

I like the creativity, though.

I'm rather fond of the basic idea of electric shifting, I think I'd appreciate (and use!) the possibility to shift from different hand positions.
Assuming a system is built with one button for "up" and one for "down" it'd be far easier to double up on the controls than with mechanical systems.

Heck, for the rider occasionally wanting to get that retro feeling one could easily stick yet another pair of shifter buttons on the down tube!

Shimano has you covered. Bring about $3500 and Dura Ace Di2 can be yours.

But only partly. Satellite switch, fine. Auto trim, great. The dual control lever looks nice too.

But as far as I can tell it's still the left lever that operates the FD and the right that operates the RD.
I'd like to see a small brain in there keeping track of which derailer to activate, leaving me to only push "up" or "down" and have the bike sort the rest out.
I'd also appreciate some sort of "auto start" feature that'd downshift automatically when I'm coming to a stop to prevent me from getting stranded in an intersection in a gear I can't effectively take off from.

Yeah, right. That would probably be more than what my bikes would cost together, if I were to replace them today. Not much chance of me spending that kind of money on a gruppo alone.

Well, I think there are some neat things that can be done functionally with electric shifting which would be nice for me as a commuter.
But D-A also has a large chunk of bling value, which I have no interest in. There's no way I'd be able to maintain the racer charade anyway....

Shimano's Coasting system was wired, but used a dynamo front hub to power automatic shifting. Again, not what you're after...

BTW, Shimano went with a wired system for Di2, not rf, because they didn't want other people to be able to hack your shifting system and, say, shift you without you wanting to during the final sprint of a TdF stage.

That would be really cool, or even (I'm a programmer), a micro SD card in the (single) shifter that would allow you to remove it, plug it into your computer, and program the auto-start's and shift preferences.

Shimano very specifically stated that Di2 was NOT supposed to be an automatic transmission.

I suppose it could be programed any way you wish when they or someone else gets around to doing it.

As to the cost, that's the penalty early adopters pay for anything. Remember the first CD players cost more than $1500. Wait until the concept moves down the range to Ultegra and 105.

There is also the Cyber Nexus 8 speed electronic controlled hub. Not wireless and the computer mounted on the seat tube by the bottom bracket actually controls the shifter cable to the hub I believe. It uses a front hub dynamo to power the system so no batteries are required. It offers two modes of auto shifting as well as a pair of shifting switches for manual gear control. Expensive though and not available in the USA that I know of except on the Ferrari bicycle. The system is shown on the Shimano Europe web site.

I've often thought the same thing, as a rohloff with a click box is just a nut to turn to change the gear... Having a stepper motor instead of cables could be really cool, and you could build some nifty shifters to fit on road bars...