I'm pretty used to driving on the left side of the road, having driven in Rarotonga, New Zealand, and Australia for several months. But I would be nervous to drive in Japan, because the roads are narrow and I am nervous I wouldn't be able to read the signs. But this video makes me think I should rent a car the next time I go there.
This video tells you about international driving permits, speed limits, rest stops, car rental, tolls, and other tips.
Video: YouTube