Many pop tunes will modulate up a semitone near the end of the piece in order to gain energy or excitement. This is known as a Truck Driver's Gear Change, and some tunes will even do it multiple times for that extra kick. I've often wondered; are there any pop (or other) tunes which at regular intervals modulate DOWN?
It seems like a good way to put your listeners to sleep, but maybe it would work in the right musical genre. (I also think it could be very funny if done correctly; I wonder if PDQ Bach ever tried it.)