As a modern concept this would look pretty fine, so you can imagine the reception the Pontiac Banshee received when it was first revealed to the world back in 1964.There's a timeless appeal to this one-off prototype, and the 1968 Corvette, Opel GT and second-generation Pontiac Firebird were all heavily influenced by it.Yet the current owner has struggled to find a buyer since acquiring it at the bargain price of $210,600 back in 2006.Longtime Pontiac collector Len Napoli has always felt he had a steal on his hands given the likes of a 1954 Pontiac Bonneville Concept sold for $3 million and a 1950 Futurliner went for a staggering $4.1 million around the time he bought the vehicle. Mr. Napoli believes the Banshee deserves to rest in a museum next to other rare and significant cars, and has been headstrong with the car's valuation, listing it just this week on eBay at the buy-it-now price of $750,000. Pontiac Head John Z. DeLorean proposed the Banshee to rival the Mustang, developing two working prototypes: a V8 convertible and straight-six coupe.The latter produced 165hp and with a 2,286 curb weight was destined to be a potent performer. Alas GM failed to sign-off on production and the project was scuttled in 1966.However, instead of being destroyed as per GM's instruction, the prototypes were hidden in shipping containers and later sold to employees.In 2007 Mr. Napoli's Banshee resurfaced on eBay with an asking price of $1.3 million and returned the following year with a $1.5 million buy-it-now price. With no bites, the Banshee was taken to the Amelia Island sale where a bid of $325,000 was deemed too low.The car also failed to find a buyer at the Mecum sale held at Pebble Beach in 2010.There are still no takers for the Banshee, but given the car's tie-in to John DeLorean, its link to other iconic GM designs and the success of other prototypes in recent years, it's only a matter of time before a suitable buyer agrees with Mr. Napoli's valuation. "I have just got to get the right person who wants a museum piece," he said.