I am seriously considering the addition of a ceiling fan to my bedroom. I had flirted with the idea when moving in; the determination then was that the ceiling was low. Ok, I apparently was looking at some other ceiling. Unless I am jumping up and down on my bed (I can't even stand straight up on my bed) it may be too low. Guess what...I lay on my bed. Maybe sit up if I'm reading or having a last minute IM-athon prior to catching the late train to slumber land.
Ceiling fans are great. They are a (relatively) quiet way to keep yourself cool on a warm day/night. Directly over my bed, a ceiling fan will serve two purposes (purpii?). The first purpose is that it will keep me cool at night. Having my a/c off during the day means I have to be home long enough before bed that my place can cool down. This is not always as easy as it sounds. Secondly, the fan would be just loud enough to provide some "white noise". I require some gentle, constant noise to relax my mind enough to sleep.
If I have guests sleeping on my couch/floor/popcorn machine I will not necessarily have to freeze them out by keeping my temperature at 65 degrees. I can warm up the thermostat to keep them comfortable and still be cool enough for me to sleep.
Looking at it written out now as I am, it seems silly not to get one.