My chocolate preferences are a somewhat fluctuating assortment. However, during tech I have to have SOME kind of chocolate -- whatever I'm into at the time, I guess. I tend to go for individually wrapped things, though -- so that if people start taking pieces, they aren't diving their hands into a bag of M&Ms and getting the rest of us sick.
Also, and this is never changing, I need Honey Wheat pretzel twists. They are so good -- perfect combination of sweet and salty. And mix them with chocolate? Heaven.