As a related issue: For those who might spend some or a lot of time in Thailand, and wish to get a Driver's License, it is a fairly simple process. For U.S. citizens with a valid state driver's license here is a decent overview:

http://bangkok.usembassy.gov/driving_in_thailand.html

I went to the DMV (Bureau of Land Transport) at the Bang Chak BTS station, and it took me ~ 40 minutes. I was able to get both auto and motorcycle licenses (separate) as my state driver's license covers both. No road-test, but you do have to pass an eye exam and response test (green light, red light, step on the brake pedal).

The initial license is good for one year, then you renew for five years. (Some Thais have lifetime licenses.)

It's an accepted form of ID here, when one is asked for an ID, say checking in for a domestic flight.