Sure they do, have you browsed through one of the skin sites?
I run from the computer to a Pioneer Premier headunit, and otherwise have simple and specific needs.
So, I made one myself that has music, GPS, a manual day/night switch, a calculator (for checking gas mileage) and a video screen, but I've never actually used the video (except in a test run). I even run the audio player as my main menu screen to cut down on complexity. A limitation of my skin because of how I want to run my system - I have my music set up so each album is in a folder by itself (not grouped by artist or genre) and I only ever play single albums, or else I shuffle through all the songs. So I don't have a lot of playlist manipulation buttons.
I've never bothered to post it up anywhere since I thought the users would be such a small set of folks.