I'm with you as far as not really caring about that...just figured if there was an option out there I'd try it. Apparently you can use LED's for the flashers, you just have to use an electric flasher plug. I just watched a video explaining that.
There are some LEDs on the market now that claim to be dimmable. I've tried some and they are not very linear, if that makes sense. I don't know if that's indicative of all of them or not.