The generation of random numbers has many uses (mostly in statistics, for random sampling, and simulation). Before modern computing, researchers requiring random numbers would either generate them through various means (dice, cards, roulette wheels, etc.) or use existing random number tables.
Yawning, swallowing or chewing helps open the small canal (Eustachian tube) which connects your middle ear in the inner side of the ear drum, and equalizes the pressure with the outer side and causes the sensation of ears popping when swallowing.
Open your mouth slightly and yawn. Open it about as far as you would to say ahhh, and attempt a yawn. Keep open your mouth slowly with your mouth in an O shape, until you break into a full yawn. Stop when you have felt your ears un-pop. Repeat if the first yawn didn't work. You will know it when the pressure re balances. You'll not only hear and feel a pop, you'll suddenly hear much clearer than you had when your ears were popped.