Ultrasound lasers (sasers?) work because the frequency is high enough to keep sound from spreading out much. I was wondering what would happen if two sasers were pointed at the same spot on a rough but non-absorbing surface? Could the interference patterns of two ultrasonic waves create audible sound from a distance?

Depends on what you mean by interference. A beat frequency could be audible; this requires the two main signals have a different frequency. You would be hearing the difference frequency.

I heard recently that directional speakers already do this. The difference frequencies make the target sound to be heard. I wonder if the speakers could be made portable so one could have a personal ventriloquial device.