If one doesn't count the 1994 season (which didn't have playoffs or a World Series), the longest streak in MLB history is 14 seasons by the Atlanta Braves (1991-1993, 1995-2005). If one does count the 1994 season, the longest streak is 13 seasons by the New York Yankees (1995-2007).
Most consecutive playoff appearances
29 Boston Bruins (1968-96)
28 Chicago Blackhawks (1970-97)
24 Montreal Canadiens (1971-94)
23 St. Louis Blues (1980-2002)
21 Montreal Canadiens (1949-69)
20 Detroit Red Wings (1991-2011)
Atlanta Braves
This is wrong- your own Answers also has the correct one- Chicago Black Hawks with 28 (1970-97).
dallas cowboys
The coloumbus blue jackets never been to the playoffs but one
The best team in the world had 19 wins spanning four consecutive Stanley Cup titles and five playoff seasons. This is a record for all North American professional sports franchises.
They have five Super Bowl wins, eight Superbowl Appearances, and are the biggest franchise in the NFL, maybe in most sports. That's why they're significant.
As of the 2007 NFL Season the Dallas Cowboys are the world's richest sports franchise with $1.5 Billion.
The NCAA basketball tournament
Man U
easy buy one
Yes, they are.
cleveland indians
The Detroit red wings with 19 going for 20 this year
Manchester United