Background:  In August of 2005, I bought a 1992 Olds Cutlass Supreme S,
3.1l V6.  Starting in October, I had trouble starting it.  It would
start with a jump, but it seemed as though something was draining the
battery.

Here's what I've done:
New battery(twice)
new Alternator
New TPS
New Positive battery cable
several parasitic drain tests by mechanics with negative results
had starter tested(tested fine)
Had the rear windshield brake light electrical thingy reset
disconnected all unnecessary lights(trunk, hood, back seat, glove box)

I took it to a mechanic for a diagnostic, he said it was a bad battery,
replaced the battery, same thing happened a week later.  Took it back
again, he couldn't find anything.  Took it back again, he still
couldn't find anything.  The next time I called, he sent his guys out
to do a parasitic drain test and check the fuses on site.  nothing.
They took the car with them to the shop.  A week and a half later, they
still couldn't figure out what was wrong with it.  I'm at a total loss!
Does anybody have any ideas?  Anything to try would help at this
point.  
Thanks,
Lissa