For those of you filming actors in a car, here's a photo of a crazy setup - if you've got the budget to do it.
The BBC One series Peter Kay's Car Share, filmed largely in the confines of a Fiat 500L, is a great example of innovative photography. The above picture shows the incredible 5 camera rig that was put together to capture those scenes. The camera mounted in the lower middle of the dash is especially interesting. It's pointed up to a mirror, capturing a two shot of the actors seated in front and anyone in the back seat. This setup gives extra extension for the two shot without mounting a camera outside of the car. There's also a large array of microphones mounted above, arranged to capture good audio regardless of the direction the actors are facing.
While many of us may not have the budget for five Canon C100 Mark II's - much less a vehicle to tow a car around that is far too rigged up to actually drive - there are some neat things to take from this. The mirror trick is one I look forward to trying!