I have heard some central American countries also have similar practices. Maybe Mexico with their siesta (http://en.wikipedia.org/wiki/Siesta).
Traditional office hours were 9-2 and 4-7 a generation ago, in order to allow people to go have lunch with their families, but even then you had to take the commute times into account. Blue collar workers only have one hour for lunch, but the expectation is that it will somehow be provided in situ.
I travel to Sweden a bit and was introduced to the concept of fika. I like it.
In the summer that is.
Our HQ office is quite remote, so if I drive 2 minutes, I can be next to the woods. I open all my windows, nap for 30 minutes with the sound of nature all around me. It's the best.
I can't wait for summer.
I've joked about giving an Ignite talk about "guerrilla napping". Here in SF I love napping in Yerba Buena Gardens with th construction workers and homeless. When I lived in Manhattan I could get short naps in the cathedrals, by learning to doze in a posture of prayer.
I work remotely, and typically take 12 minute naps either during lunch or closer to the end of the day to recharge if I feel tired.
My main advice is carry a book. You can nap anywhere if you have a thick book in your hands. "Oh, sorry. I was reading but fell asleep!"
Then again, when you're the cofounder, CTO, a multimillionaire from a previous sale, and you have a nice private office with a door that closes, you can do whatever you want.