I've used over 20 NiMH chargers over the years and for a quick, compact one my vote goes yo Lenmar Pro66. Charges independantly four high capacity NiMH cells for approximately 75 minutes without overheating. The only compact charger I know of that uses dT/dt or temperature gradient as termination method, together with the usual -dV, which, if you read cell-maufacturers literature is not recommended as a primary termination method for NiMH cells.
It's compact enough and can be powered in a car. The only thing that is missing is a discharge function, but if you run the cells to the end in your cam from time to time it will be OK