Usually, it means I'm dreaming about Val Kilmer again...
Seriously though, I've been a drooly mouth breather all my life. I soak the pillow. This has been a major life change for me.
I wear a chin strap, but I'm still drooling just a little bit. I suspect I'm sort of oozing out of my lips because of my tongue thrusting against my teeth. But until I can get a machine that records LEAKAGE, or someone videotapes me and sees my mouth is open, who the heck knows for sure?
My drool right now is pretty minor. I notice it and tend to wake a little, wipe it out of the chin strap, and roll over and go back to sleep.
And yes, I CAN tell the difference between the sweat the chinstrap develops and the drool. The drool is more viscous.