A lot of people around me were wondering why I kept asking for old broken lightbulbs...It was to do something better than throwing them away!!
I emptied them, them filled them with Kitsilano/Vancouver sand (because I am lucky enough to live 2 blocks from the ocean) and inserted an air plant (aka Tillandsia) which requires very little care.
It's a real plant but it doesn't need soil because water and nutrients are absorbed through the leaves.