Came here for a post blackjack snack (I am down overall from the trip but did just get a nice winning streak at Cosmo). Obviously I was in a good mood and wanted to see what all the hype was.
As countless others have noted, don't bother looking for signs or directions. Just head to the third floor and the path will be obvious. I'm not even sure who named the place Secret Pizza. The receipt just says Pizzeria. Now that's hip.
I got a slice of the White Pizza for 550 pennies and was very happy. Piping hot, thin-sliced, crispy, and real cheesy with ricotta and mozzarella. I tasted a little bit of garlic too. Very good and highly recommend! Note you can always add more toppings for extra $$$.