Who'da thought the Model T would be a classic in 1929?!  And the 64-66 original Mustang has already been mentioned.  Hows 'bout 2CV?
They were ************************************ cars.  Everybody had one.  So they mostly got trashed, hotrodded or left in garages as worthless.
Even the big-engined monsters from the 70s that are so 
valuable now fell to worthless when gas got expensive.  And they were terrible cars except for straight line acceleration.  I know - I had a 67.5 Firebird 400 4sp with the hood tach.
And the Speedster!  Porsche hated it and thought it was not a real Porsche.  Thank you Max Hoffman.  I remember when they were cheap used cars listed in 
Panorama for numbers that make me hate myself for not snapping one up.  And a lot were bought as DDs until they died or rusted away.  Or tracked.
I watch prices in Hemmings and am regularly amazed at the prices brought by reasonably maintained or restored cars like the 67 Mini Moke for $22k!
So do I think someone will eventually pay way too much for an original paint, numbers matching stock Boxster that has been gently used and painstakingly cared for by one owner?
Absolutely.  
