I'm flying out Dec. 20, so I won't be in DC. But, for what it's worth, Washington Metro has a new bus route from Dulles to Rosslyn and DC that runs every day, and costs $1.10 each way. The bus stop is on the middle level roadway (not departures, and not "arrivals"-- take the ramp up from the lower baggage claim level).

On Saturday, Rt. 5A buses leave IAD at 6:30am, 7:30am, 8:30am and 9:30am, then not again until 2pm, 3pm, 4pm and later. Return buses leave L'Enfant Plaza (about 3 blocks from the Air and Space Museum) at 1:03pm, 2:03pm, 3:03pm, 4:03pm, 7:33pm and later. The one way trip is 50 minutes.

Call Metro at 202-637-7000 for more info. I hope this helps.

[This message has been edited by Viajero Joven (edited 12-18-2000).]