Omnivore mentioned FlightMate ear plugs. Another brand is Ear Planes.

In any event, there was a time when I couldn't fly without *MAJOR* ear problems. Yawning, chewing gum, drinking sips of water, taking a decongestant all helped somewhat...but, since the very first time I tried Ear Planes or FlightMates, I've *never* had a problem.

(I joke now with friends that I won't even drive past an airport without them!)

If you use this kind of ear plug, the trick is, IT MUST BE IN PLACE IN YOUR EAR BEFORE THE PLANE LEAVES THE GROUND! It does absolutely no good to wait until you have a ear problem to put them in.

Good luck!