I regularly fly out of Boston at 5:45 and 6 am. With the consumer protections in Massachusetts, and with Logan Airport so close to the city, it's unlikely to be flights much earlier than that.
But with the security delays/requirements, along with the 1-hour trip it takes me to get to the airport, I'm up at 3:15 am to take those flights.
[This message has been edited by rkt10 (edited 08-09-2003).]