After seeing all the replies in this thread, I have to add this two to my most like (useful) list:
0. Radio - I wont buy a car that doesn't have AM radio
1. Cruse control - I wont buy a car that doesn't have cruse control
1.5 Head light on warning when car is turned off
1.6 Radar detector. I don't speed much these days, but it keeps me alert.
2. Trip computer (I particularly like my previous VW's), dual, one manually clear/set and one automatically clears and restart after 2 hours (presumably new trip) displaying MPG, Miles, time.
3. Exterior temperature display (don't care when in the Summer, but rely on it in the Winter)
4. Stop watch - I found I use that a lot. In fact, I would like it dual or multiple ones. With a tie to trip computer is also a good thing but in that case I want more than dual.
4.1 Dash cam - I don't have one, but I wish I did when some lady turn right from the left lane. I saw her and I came to a complete stop, but she forced on and crush my left front fender. I had the luck of getting an auxiliary policeman responding. He refused to just walk up 20 feet to see that the left lane was no-turns-allow. So the whole thing was a mess.