For those of you who are not as familiar with quantum physics - there is a tiny particle called a gluon - (Glue - on). So its a play on words - you want to make sure to put glu-on his name plate so it doesn't fall off [his office door]. Up, Down, Charmed & Strange are tinier particles called quarks which are inside of protons and neutrons (they are the smallest units of reality that we know of today outside of string theory). Strange was the name of the new employee that was starting today.