We've all heard of or even own electronic shifting but now there is wireless shifting and even wireless dropper seatposts for mountain bikes.
Shimano had a programmable derailleur system for mountain bikes where you could control both front and rear derailleurs with a single switch and you could program it to change the front when it hit a certain cog in the rear. Unfortunately for Shimano, one by systems took over and nobody wants front derailleurs on their mountain bikes anymore.