You're going to love Syd Segal's astute rendition on the classic effect by Bill Simon. A spectator freely touches four cards in the deck which are removed and shown to be the four aces.
The method is clean, simple, and very direct with no sleight of hand visible to the spectator.
I have done routines after Effective Aces that just were not as powerful as these and the spectators would, after 3 or 4 tricks, be puzzled by how the four of a kind was introduced in the first place.
The method itself is very clever and, after some practice, easily achievable. And something important is that it has a clean ending. I mention that because, usually people want to see the aces in their hands.
Great utility effect!