Well my advice next time is to take your camera along.
On my last drive back from Marigot to Roseau I had the luxury of being a passenger for a change so I spent the whole journey amusing myself taking photos of car rear lights, head lights and street lights.
You may get some strange looks from whoever is driving but the results can be some pretty cool abstract images.
It works best when it's very dark, you move the camera around a bit and you use a slow shutter speed. Also try using the camera self timer as well.
Here's some examples of a few I took:
Click for Slideshow - Camera Light Painting effects
During the day you can also get some nice blur effects of the scenery as you drive past too.
Click for Slideshow - Camera Movement effects
