I assume you're looking for a serious answer.
Pick a situation and turn it into a game in a small area. The NJD are probably the organization that most popularized the concept. In fact, one of the games we use is called New Jersey. Basically, it's 1-1, 2-1, 2-2 keep-a-way in an area about 10X10 or so along the boards. The theory is everything a player needs to be successful needs to be done in a small area.
You can also think organized shinny hockey, to coin an oxymoron. For example, we will put the net against the end boards or in the corner and have the guys play 2X2 inside the goal line. We also add conditions like a team has to make a pass to a coach/player playing outside the area to go on offense, or the must make two passes or make a bounce pass off the boards before the can shoot. We sometimes add a player in a "safe zone" and the team on offense has to work a give and go with him before a shot can be made. The variations, once you think about it, are endless.
Another great one is put two nets back-to-back between the blue line & goal line. Play 3X3 with one goalie and the goalie has to go back and forth between the nets. They hate that one.
The key is to 1) keep feeding pucks as goals are scored or pucks leave the area, 2) keep the times short (we do 30-45 seconds to simulate shifts), 3) make it situational, and 4) make it fun.