Or you just sit there and roll the dice and raise your eyes, or mutter an "OOOOOOOH!" as well as "No..." or "Not good!" and never ever give them something to focus on, just say, "it" always be so vague so you let the players minds wander and build up the angst of the unknown!
I had one actualy ask me once "What are you rolling for?" I was honest, "Nothing, just ta freak you out!" Then, when I started rolling copious like, he was at ease! HAHAHAHAHA!!! Until they ran into a far ambush at a bend in the road with a quad ZSU and a rapira towed gun. I had been to generous and they had to many vehicles so I had to weed em down
