O.K, here's an interesting one:

The leak that caused the '87 to limp home last night was NOT from the 
driver's side hose, it just looked like that in the dark.  It really
was all over the place, somewhere between a drip and a continuous
stream. 

I had also mentioned that I found the bolts that attach the intake
manifold to the cylinder head loose, especially on the driver's
side... 

After I discovered that the leak was not from the hose, I proceeded
and tigthened the  bolts to a 'reasonable' tightness ( I do not really
know how much they should be torqued).   I did this while the engine
was running (dangerous, I know, but I wanted to see if it made any
difference), and I found out that for about 15 seconds there was a
gush of coolant, then zero.  I kept the  engine running at about 2200
rpm for another hour, nothing.  The coolant stayed at the same level,
everything around the engine dried out, there was not even the
coolant smell left.

What happened here?

It may be that the bolt for the intake manifold had nothing to do with
it... About 6 months ago, mistaking a cracked T connector for a leaky
head, I had put the Bars Leaks stuff in this engine.  I wonder if some
of the leftovers just happened to find their way to the leak and plugged
it?

Anyway, I'll appreciate any help in resolving this mystery.  The bus
runs fine now,   I drove it around bethlehem another hour, no coolant
loss, no bad smell.  However, I'm still afraid of taking it for my
daily comoute, which is 60 miles each way...
Thanks,
Cetin