The airline monitors should have the boarding information on them, it's stupid that they do not when there are delays. Even if it was just changing the color or blinking the flight or something.
Even one of those numbered boards like some restaurants have, where they light up the gate number (waiter/waitress number when food is ready) in the clubs they don't make announcements in would be a huge help, or a pager like you get when waiting at restaurants when your table is ready.