I think it was Larry Jennings who said, "every good trick should have a discrepancy".  (If it wasn't Larry Jennings... oh well, every good magic trick write-up should also have a discrepancy, I guess).  Anyway, whoever said it would be very pleased with Ron Frost's trick, ACE-TRONAUTS.  Because it has a couple of discrepancies during the performance, but it also proves the adage, because the discrepancies fly by an audience of laymen without notice. 

The effect:  magi shows four faceup cards -- all Ace of Clubs.  He counts them from hand to hand, and one of them turns facedown.  He counts them again, and a second card turns facedown.  He counts again, and a third is facedown.  The fourth card (or Ace-tronaut if you use the silly patter supplied with the trick...) is too scared to turn "go through the time warp" that turns cards facedown.  So the facedown cards are turned faceup and they are now blank.  In the end, the blanks turn back into Aces, but all the pips expand into giant size center-pips.  (see photo)

The discrepancies?  Well, sometimes the faceup ace is in a wrong position during the count, and also two cards are turned facedown, but all three cards are facedown after that.    Discrepant, but in the actions of the handling, they are not as noticeable as I just made them sound.  

I remember seeing the giant pip cards (in a line illustration) in an early Top Hat Topics flyer from Tannens back in the 1980s, and I thought they were cool then.  I still do.  This recent manufacturer version of the trick is made with specially printed Bicycle poker cards -- high quality and easy to handle.