Dirty plays or cheap shots in any sport are absolutely unacceptable, but unfortunately they still occur regardless of what rules are put in place to prevent them from happening.
One of the more recent dirty plays that has gotten a lot of attention happened during a Synerglace Ligue Magnus hockey game (French league).
Holden Anderson was the player who delivered the cheap shot to Julien Desrosiers after his team's 4-3 win in the fourth game of the quarter-finals.