Nick Leddy was traded by the Blackhawks to the New York Islanders in a move needed to clear salary to maintain some flexibility under the cap and the Islanders needed some veteran help on what was looking to be an extremely young blue line.The Isles traded to the Hawks defensive prospect Ville Pokka, defenseman T.J. Brennan and restricted free agent goaltender Anders Nilsson. New York also got goalie prospect Kent Simpson as part of the return.Leddy will be playing on a contract that expire after this season, and the Isles paid a fairly high price. That said, New York is deep on youth in their organization, which makes some of those picks and prospects a tad more expendable.Leddy, 24, had 31 points last season as a bottom-pairing defenseman for the Hawks. The former first-round pick of the Minnesota Wild, has appeared in 258 NHL games, all with the Blackhawks, and has 93 career points in the league. He has 54 games of postseason experience and was part of the Hawks 2013 Stanley Cup team. Leddy will be a restricted free agent after the season ends.Boychuk instantly improves the team’s ability to defend and their overally physicality, while Leddy brings another power-play weapon and will likely get more ice time in New York than he could on the Hawks deep blue line.You really have to commend Garth Snow for his ability to exploit two cap-strapped teams for everyday players that are going to help the Isles immediately.The Bruins take on no additional salary, which was the goal after the B’s had zero cap flexibility thanks to the bonus overages from a year ago. Bruins fans are likely to be disappointed by the return, but Peter Chiarelli had little choice with the cap situation.The Hawks build onto their already deep prospect pool on defense with Pokka. Brennan, who has bounced between the AHL and NHL over the last few years is a good option as a potential cheap call-up. He had 72 points for the Toronto Marlies in the AHL last year and has 40 games of NHL experience. Nilsson is currently a restricted free agent without a new contract. He is currently playing in the KHL, so the Blackhawks would merely retain his rights without having to spend the cash. In a bid to get tougher, the Blackhawks are bring back Dan Carcillo, who signed a one year contract.