Give this one a shot if you like pumpkin. Really rich stuff. I had to add more ice cream than it called for to get it to the right consistency.
http://www.howsweeteats.com/2011/09/grown-up-pumpkin-pie-milkshakes/
http://www.howsweeteats.com/2011/09/grown-up-pumpkin-pie-milkshakes/