This is a rotating pen/pencil holder. Each cylinder can hold 2 pens, maybe more based on the pen size. This is fully 3D printable without any bearings required. By minimizing the amount of contact surface between the base and the holder, you can get very easy and smooth rotation without the need for bearings. Tested with PLA.

Prints in 2 parts: the base, and the holder. The holder just slides on top of the base and is held by gravity. Does not need supports