BMW did this in the 7 series and I think some 5 series. A row of buttons in the center console that you can choose what they do. Unlike old style "preset" buttons they have a sensor in them to detect your finger being on the button before pressing it, and then it shows at the top of the iDrive screen what that button is programmed to do. I thought that was quite an elegant way to fix the "can't remember what I made this one do" issue you get with programmable buttons.