Make A Hologram Of An Object That Doesn’t Exist

MedCosm CGHMaker (computer generated hologram construction kit) is software that will calculate what the interference pattern would look like for a given object and then allow you to print that interference pattern onto a cheap overhead transparency to make your own hologram. Said hologram can then be projected with a cheap laser pointer for viewing.
Knowing how difficult it can be to produce a hologram (huge sand tables to prevent vibration and other setup are not unusual), this looks like an easy way to play with something fun.