...and upon a quick search of "Parade of Progress", I discover its a GM Futurliner. I saw it on I-96, going East (I'm in Michigan). Using the web address on the trailer, futurliner.com, I found out there's a show in Milford, MI, July 19-20, so that's probably where it's headed.
Thankfully I am developing amazing cellphone picture taking skills, because my eyes were on the road while taking it. They came up pretty well I think.
Anyways, that car is a beauty, I feel honored to even see it because it's apparently rare.