i replaced a bulb over the kitchen table the other day and thought there must be something cool i could do with the old bulb, so i looked around online and found this website. this is what happened! i made the sand and and shell one first, and that made me think of trying water inside my next one.
this is a fun way to reuse burned out bulbs (: but wait! before you go running around the house looking for broken bulbs, look up how to safely "gut" a light bulb. don't hurt yourself!
i'm sure there are many other things that could fit inside the top of a light bulb, so be creative!