Here's a sim you should definitely put on your must-visit list: Heiankyo. The landing point is a bridge that takes you to a Japanese shopping event, but if you go in the opposite direction, you will soon reach a traditional Japanese village, and then some more.
The village also contains stores where you can buy typical Japanese items, such as kimonos or various food items and utensils, many of which are sold at a highly symbolical price. I found a few interesting freebies whose actual use I have yet to google. Without any additional information available, for those like myself who are not well versed in Japanese culture, the place will be rather enigmatic.
Deeper in the village, there's a complex of what looks like temples, or possibly palace buildings. Everything has an air of authenticity, but to really get the most of it, it's probably best to bring along someone who would be able to explain all the little details.
The most intriguing part of the sim is the parcel named 'Japan Horror', found up in the mountains overlooking the village. I'm guessing it contains references to stories from Japanese folklore and mythology, and I'll try to find out more about them. Here, you will find eerie ruins and altars, signs and talismans, but also things like decapitated heads and a giant skeleton. It felt like the Japanese version of Halloween!
There's also a "lucky cat", which I recognized to be maneki-neko, although I've never seen it in this size. In any case, it was a pleasant sight for Duncan and me, as we both adore cats.
Although the cat is supposed to bring luck, soon after we managed to find ourselves at the bottom of a very deep well. So, watch your step while you're up on that mountain!
I don't know how long will the sim be open - one never knows in SL - so do take the opportunity to look around while it's there.