I used my newest favorite tip tonight and thought I'd share it.
When running a rock show or other loud show that you can't hear the ClearCom due to the PA, wear disposable ear plugs under your headset then crank the volume on your beltpack. Seems counter-intuitive, but it works. I have no ringing in my ears tonight at all tonight, which I often do after a rock concert.
This was taught to me by the guy who runs http://www.roadierags.com/shop/ a very cool site.
Anyone have any other "quicktips"?