This clip uploaded by YouTube user MrBibio shows water droplets appearing to float in midair. While it sounds like magic, it's actually an optical illusion created using a tube, a piece of tape, a speaker, and his camera:
[Y]ou're actually seeing 25 different drops every second, the uniformity of the waveform being played through the speaker is vibrating the pipe in a uniform way, so the drops exit the pipe uniformly, the frame rate of the camera is synced with the speaker so the drops appear static, the short shutter speed means the drops appear sharp and frozen in mid air, a longer shutter speed would show motion blur.