The phrase "a can that projects from a vertical support" is a riddle, and the answer to the riddle is "a flagpole". A flagpole is a vertical support that can have a can projected from it. An example would be a flagpole with a can-shaped container attached to it, which could be used to hold a time capsule or other small items. However, it is worth noting that the phrase "vertical support" can refer to a variety of structures, including posts, stakes, and columns. For example, bridges have vertical supports called piles, which are hammered into the ground and used to hold up the bridge. Additionally, some patents describe vertical support structures that include mounting plates and support members.