Here we go...
Drink every time:
- There's a musical cue that is so suspenseful that you wonder what show the music director is watching.
- Jack makes demands of someone that has all the power
- Jack decides to get into a fight with someone for no reason
- Someone says "I'll go along with you" with no explanation or motive
- Someone asks an absurdly probing and insightful question for no reason
- Someone explains they can't answer a question because there's no time, when the characters are hiking across the island
- Jack does something that should kill him
- The plot changes purely so Kate can switch from Sawyer to Jack or vice-versa
- The camera goes from Kate's face to Sawyer/Jack's face to show that there's sexual tension, even when the characters aren't looking at each other.
- Someone believes a lie even when the person is a known liar or is the enemy
- Someone believes a lie because it's so completely absurd and implausible
- Someone implies that they know anything about the island and it's not true. (Spoilers: it's not true every time)
- It turns out there's another facility on the island no one's seen before