Speaking from experience, it is possible to take DC public transit to reach the light rail. However, This involves taking a bus. While that may not sound like much, I do recall the MTA bus route maps being a HUGE pain to interpret, and the buses just sort of show up whenever, instead of on schedule. So, if someone is feeling really brave, they could fly into the Reagan and take public transit all the way up to Baltimore via Metro -> MTA bus -> Light Rail but this will be a pain in the neck and will involve quite a bit of planning to make sure that all of your transit is within the operating hours of the Metro, the MTA bus, and the Light Rail.
That being said, when is this meet up?I've been on the forums for a while and I've never attended a meetup. My money's a little tight right now, but I can bring Vodka.
I just moved back to the DC area to stay and I figured it would be nice to meet some fellow Playgrounders in the area. I know I haven't been the most active poster, but I'd really like to join in on the fun if you'll have me.
[EDIT]
*DERP*
But I can still bring the Vodka, yes?