I was driving home from UMBC today when I noticed this driver drifting uncomfortably close to my vehicle so naturally I blew my horn. The driver swerved back in their lane.  This same driver kept going over the line in my lane so I began to think that the driver was intoxicated.  I sped past the driver to get out of his/her way and looked over to see that it was an elderly woman who could barely see over the steering wheel not to mention her head lights weren't on (7:00pm)  She was driving about 20 mph.  I guess she was around 80-90, years old.  I didn't know the woman personally but I slowed down at the red light to tell her to turn her lights on and suggest that she don't drive late at night because it's dangerous for someone that age.  Which brings me to this question, should there be an age where retesting for a drivers license occurs?  Elderly drivers pose a risk to themselves and others, if I wasn't paying attention, this woman would have hit me.