If any of you visit St. Louis be sure to go by Ted Drewes frozen custard. This is a route 66 landmark outdoor frozen custard stand that is kosher (not cy) under the Vaad Hoer of St. Louis.
Frozen custard is like a thick rich soft ice cream. They make thick shakes called concretes that you have to eat with a spoon.
They are open very late almost every night (well past midnight).
Word of warning: Almost everything is kosher however be sure to check the Vaad list on the front of the stand since a few items are not.