If you put a droplet in an ultrasonic field, you can make it levitate.
Increasing the acoustic pressure flattens the drop.
And by changing the strength of the field, you can turn it into a star with different numbers of points.
The higher the field strength goes, the more points the star gets.
Until it all gets a bit too much.
Watch the full video and read an explanation here.
View this video on YouTube
There's also a pre-print scientific paper available on arXiv.org.