I have one of these under my desk in my office.  It blows up at me and doesn't mess up the papers on my desk.  On the low setting, it isn't too loud, but the high settings are quite loud.  I wish it has a super low setting, but it doesn't.  Knob on the back adjusts off-hi-med-lo and a button on top adjusts rotation.  It can also be angled up and down.  Mine has been in use of a couple of years without any problem, so it stands up well to heavy use.