Travel extras, no travel essentials. When assignments bring you out on the road, there are a few items that are must haves.
Most rental cars now have an AUX IN on the stereo and while searching stations in a new city can be fun, mostly it is frustrating as you are navigating new roads. Keep an 1/8 inch mini jack audio cable in your travel bag and enjoy music from your phone, iPod or iPad; clear reliable hi-fi.
A USB lighter adapter is the next essential. Use it to charge your phone, power a TomTom or charge a GoPro (and many other cameras) on the way to the shoot. I keep it in my computer bag and share the cables. One more note; there are some that are shorter and easy to pack, BUT may NOT be long enough to make a good connection in all makes of cars. I learned this the hard way.
550 paracord. Honestly, I laughed when I heard the concept of wearing a rope bracelet to save your life, but the stories on survivalstraps.com may surprise you. Pulling a branch out of the view of a shot, wrist strap for water rig and securing grip gear is how we use it regularly. As safety lanyards on auto or roller coaster rigged cameras, it offers an increased piece of mind.
And finally, you need a knife. This one has been in my camera case for more than 10 years and just a few weeks back the TSA in Lincoln, Nebraska said I could not board with it in my bag. Best part of the story, they sent it to my studio, no charge. Thanks guys.