My ears never cleared without popping them myself. However, yawning always gave me an instant perfect equalization. The answer is obvious, ask crewing to fly you with the most excruciatingly boring colleagues in the airline.
Seriously though, give it time, and if you can get somewhere warm, see what your doctor thinks about swimming in salt water - i.e. you are not wide open to other bugs etc.. No diving though!
I always found it good following head colds. Failing that, sterile warm water doosh with enough salt to taste roughly like the sea. Not very scientific, but is one of those old remedies that seem to work well.