Another option would be to ride up to Gallows Road, park your bike at the Metro (Dunn Loring) and ride the metro in. Or go to East Falls Church and then ride the metro in. If you want a shorter bike ride. If before 7, you could take your bike on the metro and then ride home. When the weather isn't that great in the morning but its suppose to be good in the afternoon, I'll ride the metro in and then bike home.

I go into DC from near the Vienna Fairfax metro. At Ballston I go onto Fairfax Ave and follow that down to Courthouse to miss the hills in the morning. Not too much traffice around 6 to 6:30 AM when I'm going in. Coming home, I just take the Custis and the hills so I don't have to deal with the traffic.

Have fun, John