Actually, since you will be traveling during the weekend, you might be able to use the HOV lanes, depending on where you are going. I-395 & I-495's "reversable lane" is open to all traffic on weekends and goes either Northbound or Southbound, according to a schedule.
If you ask me, the signs on the weekend are real confusing if you are from out of town, as the say:
RESTRICTED LANES (with the HOV triangle symbol)
Open to all traffic
Link to the HOV lane Schedule