Will And The Won'ts - The Midnight Special 

"The Midnight Special" is a traditional American prison song written some time near the turn of the century. John and Alan Lomax, while working for the library of congress, recorded Leadbelly's version (while he was in prison) and erroneously credited him with the authorship. The "Midnight Special" was a train that passed by the Sugar Land prison in Houston, Texas and when its light shone upon someone's cell, it was considered a sign that they would soon be set free.