Overspeed hockey drills are ones that force players to move their feet faster than what they are comfortable with.  When you are looking for a high tempo practice then starting the practice with a series of overspeed drills can be a good idea.

Depending on the type of practice you envision you most likely have a bank of drills that you call upon.  I typically like to gear the warm towards the practice so that the warm up will not only get the heart pumping a little bit, but also lead into what we will be working on in that particular session.  For example, the day before a tournament or a big game we work on special teams quite a bit. We like to use a warm up in which the players are passing and receiving the puck a couple hundred times.