Sploat by Alexander Smith
Imagine being able to borrow a deck of cards and spread them past what would look normal. Then let go of one side of the spread and the cards float, just inches away from their face. This is Sploat.
-examine them before and after
-NO threads, wires, magnets
P.S. (the trick is not completely impromptu, you will need to purchase a minor prop or you might already have it)