Two: Because of internationality and American influence, Okinawan vending machines (which seemed to appear every thirty feet) are sometimes stocked with stuff you don't see anywhere else. (The same reason you can get taco rice there)
Three: Shisa, called shishi in China, are guardian lion-dog creatures that are often seen in pairs at the entrances to homes or other gate-structures. Usually, one has its mouth open and one closed. I have read different explanations but my favorite is that the open mouth is the "a" and the closed is the "m" representing the first and last sounds of the universe.. in English generally written as the "om" which is mantra-tastic. Also, sometimes one has a ball (the male?), and one has a cub (the female). I find it significant that they are protectors, but apparently they are known to be really rough on the cubs (squishing them with their paws, throwing them off cliffs, etc. to test their strength) as well. I love them because about ten years ago I had a dream about a creature strongly resembling a lion/dog which played with me in an enclosed courtyard. It threw me against the stone wall, and when I was really put-out about that, it assured me it was "just fucking with me," turned into a young woman, and promised to be my protector for ever.
Shisa are just everywhere in Okinawa, in all forms of fierce and comical.
Four: The local beer is Orion. The local sake is Awamori, and it's special because it's brewed from Thai jasmine rice instead of mainland Japan rice. It's strong, but I did buy a bottle of a mix of it and umeshu (plum wine) that is excellent.
Two of the other varieties of Orion: Rich and Southern Star. Mugi is still in my fridge because I tucked it into my carry on before getting on the plane..! Also featured, special pineapple-shiquasa chu-hi, not to be confused with hi-chu, which is also sold in these flavors and only in Okinawa.
Five: Famous foods include goya, a bitter gourd melon thingy, and the champuru style of cooking in which you kind of just throw everything together at once. Which is so my style of cooking. So it's probably more involved than I just said.
Six: There are MONGEESE. Mongooses? Someone said a must-see thing would be a mongoose fighting a snake. Word. Apparently, Okinawa has a couple poisonous snakes. Or rather, apparently, mainland Japan doesn't really.