Instructables user Imnopeas shares a handy way to make shot glasses out of a cucumber using common kitchen knives and an apple corer. Simply cut your cucumbers into 5cm sections and use the apple corer to create a cup. Make sure you leave at least 1.2cm of solid cucumber at the bottom to avoid leaks.
These seem like a great addition for outdoor parties; if drama ensues and your shot glasses are lost or thrown you only have a piece of cucumber in your yard instead of broken glass.
Organic Shot Glasses [Instructables]