A friend told me a story about how in LV there are "walkers" -- folks who walk around the casino floor -- looking for unplayed credits and games with bonuses waiting for a play.
Years ago at NYNY there was a slot called break the bank (or something like that) where three wins of some sort will turn the combination to open the vault and some bonus. And we would try to find a machine with one or more of the wins were left making the bonus easier to get.
Now my friend tells em that that are players scouting the Ultimate X machines (a variety of video poker) looking for games where a bonus will be played on the next hand.
obviously you don't want to abandon a machine when a bonus is about to be available but I guess some people do run out of money or run out of time. (Running out of money is more likely.)
Well, my friend told me that at one casino on the The Strip there were at least four of these counters who kept coming by the Ultimate X machine near him to check... and they came one after another.
Sound familiar?