The only thing I've ever lusted for (and not in my current car) are a current-gear indicator, and a shift light.
Err why? =\
The only thing I've ever lusted for (and not in my current car) are a current-gear indicator, and a shift light.
Err why? =\
A clock

Cost per mile in pence calculated from MPG and editable fuel price

Get it to tell you what the weather is like!
Outside temperature.
Precise amount of fuel in the tank (litres).
What mcu are you using for the project? Hardware canbus would make life very easy but i've not seen many chips which have that while being in a hobbyist friendly package.
I have a vague plan to augment air con to climate control, part of me thinks it would be cool to have servos on the heater controls to control it but I want to have a look at the cars data buses and see if I can hijack that for a stealthy install
