Bum shower
Bum showers are found throughout Finland in toilets. They appear to be a variation on the French bidet and are showers attached to the wall next to toilets. It's very difficult to figure out how to turn them on.
The Colonel's Regiment found one in their hotel room during Mission 12 
12 Helsinki. After spending a day in ignorance, David eventually managed to operate it by turning on the sink tap, then depressing the trigger on the bum shower. This enabled him to alternate using the sink and the bum shower. He gave Mike and Steve a running commentary of his exploits, exclaiming, "Sink. Bum shower! Sink. Bum shower! Sink. Bum shower!"