Make a sink (just add a lever pointing down above) or a trash can out of a hopper connected to a dropper or dispenser. If the items cannot reach the outside for other players.
or empties the items to something which destroys them(such as cacti
etc.). Attach a hopper to dispenser by sneaking
fire on netherrack
lava
then place the hopper. This will not work without sneaking. One wise idea is to have entrances to secret rooms in this room.
Dye room
A nice room where you can store dyes and clay. Typically only has to have one chest.