Kupo KD302112 Baby Drop Ceiling Adapter with 5/8" Stud is a favorite for trying to find a suitable mounting point on drop ceilings.
The drop ceiling mount, also commonly called a scissor mount, attaches to an intersection in the metal grid that supports the tiles. It remains a must have accessory for shooting in office buildings.
The male version of this adapter features a 5/8" baby stud for mounting light fixtures or any accessory with a 5/8" (16mm) receiver.