One of the more challenging things to light is glass (and other highly reflective surfaces), because normally when we photograph a subject we are putting our light on that subject.
But with glass we do the opposite, we are lighting around the subject.
You will find a couple well done tutorials for lighting glass here and here.
Now I'm off to Nikon Pro Photography seminar to stare and drool.
Funny, as I get older the things that make me go "hhhmmmm" change. ;)