The scene that gets me the most
When they toss the cells and Norton takes and nearly walks off with Andy's bible.
Only at the end of the movie when it reveals what Andy was hiding in it, does it become apparent how tense that scene really was (the audience just doesn't know yet).
I can't imagine how Andy kept his cool in that situation. Any normal person would've shaking, sweating, puking, or otherwise signaling something was amiss!