At the bar, when Penny tells Beverly she's sleeping with Leonard, the position of Beverly's hand on her shot glass and the amount of liquid in it changes between shots.
At the bar when Penny and Beverly are drinking and Penny orders the final shot, she drinks it as soon as it's poured. The angle changes and the shot glass is suddenly filled again, even though no alcohol is poured into it, allowing Penny to drink it again before they leave.
Sheldon says he liked the Grinch, right up to the point he decided to save Christmas. In episode S2E22 he sarcastically told Stewart "said the Grinch to Christmas" when Stewart apologized for something. This indicates he had already seen the movie and in fact didn't like the Grinch ruining Christmas.