Originally Posted by gemac
I believe that the 3 hours refers to the flight you want to take, not the one you are ticketed on.
Bingo:
Search "standby" on AA.com and you'll find the answer.
RichardInSF, there is no need to worry about multiples of $25. One payment of $25 will do the trick.
Edited to delete link, since I believe it contained access to my account.