Japanese women are embarrassed by sounds made while in the bathroom (in short, the sound of pee). I really don't understand this. It's like being embarrassed that you can hear your footsteps while walking down the street; what other sounds would you expect? In any case, because of this embarrassment, Japanese women will flush while they're making use of bathroom facilities - one, two, sometimes even three times total. It's an awful waste of water.
In an effort to get women to stop wasting water, Japan did a wonderfully astute thing. Knowing that people are loathe to change their ways, they didn't encourage women to stop flushing. Instead, many places have installed motion-sensitive speakers in the bathrooms. When you sit down, these speakers automatically play a water-sound to cover up any noise you yourself might be making. Sometimes it's just white noise, but if you're lucky it's a flowing-river soundtrack, complete with the occasional bird chirp. These are usually to be found in more urban areas, of course - out in the boonies, expect to hear constant flushing. I find them hilarious and have a hard time not giggling whenever I come across them.
3. Washing Up
Once you're done with the toilet, there's washing up to consider. Two things are inevitably missing from the sink area: something to dry your hands with and soap. There are exceptions, of course, but it's generally assumed one won't find these things. The Japanese tend to carry a small towel or handkerchief for drying purposes (a green practice that I hope will spread), but the absence of soap continues to confuse me. There seems to be an opinion that water is enough, which it isn't. Antibacterial hand gel, anyone?