My 2 year old Maine Coon just started drooling excessively for the past 4 hours!?

My cat normally drools a little bit when purring and content. But today I've noticed her drooling excessively. When I carry her my arm gets wet and the saliva just leaks from the side of her mouth. The drool has no odor and is clear. All of her teeth are in great condition and to tell you the truth she seems fine. However, this is very unlike her and I am worried. What could be wrong? Could she have ingested something? If so, what can we do next? Is she sick? I can't do anything until tomorrow. Help!