herf-a-dor, otterbox and I think Xixar all make travel humidors. I have a herf-a-dor that holds 5 and a cigar caddy that holds 15 or so smokes. They work for my needs. Which is only weekend car trips but I don't leave it in the car when I get to my destination. The temperature regulation may be an issue in hot weather. they are all black and plastic so I'm sure the heat would rise in them. Just do a google search for travel humidor and you'll see whats out there. There are so many kinds.

**I got the Herf-a-dor as part of a combo deal on cigarbid for around 20 bucks. 5 cigars(monte media noche) a crappy butane lighter and the travel humi. not a bad deal