(1) Cam Neely
Often remembered as the prototypical power forward, Cam Neely was actually a big wuss, who wimped out of his NHL career earlier because his knees hurt a bit. He only played 726 NHL games, but through a series of underhanded deals with shady characters, he managed to buy his way into the Hockey Hall of Fame. That's right folks, there's a guy in the HHOF who is most famous for the attempted err... assault... of Jim Carrey in Dumb and Dumber.
All that aside, the Cam Neely era in Boston was the only time in history where the Bruins had a considerable advantage over the Montreal Canadiens in the playoffs. Neely was a thorn in Patrick Roy's side in particular, with the latter saying at the conclusion of his career that there was no one in the league he hated facing more.
(4) Wayne Cashman
A lifelong Bruin, Cashman wasn't the most talented player in the league, but he was one of those guys who just wouldn't go away. During the 1970's when the Canadiens absolutely dominated the NHL in every way, shape, and form, Cashman was the jerk who continually scored at annoying times to keep the Bruins in games they didn't deserve to be in.
As if that's not enough, when Cashman retired as a player, he went into coaching at the behest of another Bruin, Phil Esposito. His only head coaching job was with the Philadelphia Flyers, which is gross enough, but he also served as an assistant coach for Marc Crawford for Team Canada at the Nagano Olympics in 1998. Considering Bruins bias, he's probably the guy that chose Ray Bourque to shoot instead of Wayne Gretzky. It's the only explanation that makes sense.