Self tuning guitars aren't new, but this is the first gadget I've seen you can have installed in an existing guitar.

Although it's "only" $800, none of my guitars cost that much. Self tuning guitars are something I think would sell well with those only just starting up, but not for that price.

The pros will love being able to swap tuning in the middle of a song.

I particularly like this one because it's control is a knob just like the guitar's volume and tone knobs.

Tronicle PowerTune from Synthax.