Is there a way that I will be able to get from Washington, DC to Baltimore after midnight using public trans?

I will be in DC Friday night and I need to get back to Baltimore. I won't be finished doing my job until 11:00 p.m. I know I can catch the B30 but I am not sure if it runs that late, and I know that the MARC does not run that late nor does it run on the weekends. Is there any other way I will be able to get back to Baltimore, or at least to BWI?