Cardassians raiding Earth for its precious brake fluid?  Seconding a previous
response I would say sniff your carpeting and floor boards, and/or look for
a film of brake fluid all over drivers side front suspension.  You're not
looking for a puddle: it would take a long time and a huge quantity before
drops start to make it off the car.  Like some others of us, you should
probably get resigned to having sticky wiring under your dash as that is 
probably where your leak has been.
B.