On the flip side of the coin, airline reservation systems use a
minimum connection time of 45 minutes. They won't let you make a
reservation for a shorter connection time. You can get around this by
buying two separate pairs of round-trip tickets to/from the
connection, or by booking different legs on different airlines, but if
you happen to miss the connection, the airline is under no obligation
to rebook you on a later flight.

However, if you travel light enough that you can carry on all your
luggage, and you know the connecting airport, trimming the connection
time can get you to your destination faster. If you get to the
connecting airport on time or early, you might try going to the gate
of the earlier flight to your destination, and ask to be put on. If
the flight isn't full, they'll probably let you board.

Some travel agents and airline ticket agents will sell tickets that
have less than the "legal" connection time printed in the schedule,
but whether they'll let you do this depends very much on the agent.

Some parts © 2009 Advameg, Inc.