Some are considered bush league (which I do not endorse), but most are legitimate way of deeking or fake outs to trick baserunners.
Stealing when a batter tips a foul ball into catcher’s glove
Unless the foul tipped ball gets away, it’s a strike so the baserunner’s stolen base is valid. Some opponents may call out foul ball and try to trick the runner into going back. At that point, the defense can tag the runner out since it’s a live ball
Deeking the base runner – Derek Jeter
It’s important for a base runner to know where the ball is hit. In this particular case, a runner on first was running to second based on a fly ball but Jeter pretended that it was a grounder and motioned for a double play, which forced the runner to slide.
See the video here:
In actuality, the ball was caught in the foul territory by third base and by the time the runner realized his mistake and tried to go back to first, the ball was thrown back for an out.