Currently... The Detroit Red Wings (20 years straight and continuing).
Currently (2011 season), the longest ever playoff losing streak is 7 straight games by the Kansas City Chiefs. They lost the 1993 AFC Championship game to the Bills, 1994 Wildcard to the Dolphins, 1995 Division to the Colts, 1997 Division to the Broncos, 2003 Division to the Colts, 2006 Wildcard to the Colts, and 2010 Wildcard to the Ravens. Many teams have lost 6 straight including the Giants (1939-1950), Browns (1969-1985), Vikings (1988-1996), Cowboys (1996-2007), Lions (1991-1999) and Seahawks (1984-2004). The Lions streak is current as they have not made the playoffs since 1999 when the lost to the Redskins in a Wildcard game.
Mickey Mantle's longest hitting streak was 16 games.
Through the 2008 season, that distinction is held jointly by the Buffalo Bills and Detroit Lions whose last playoff appearance was in the 1999 season.
The Boston Bruins' longest streak was 14 games from December 3, 1929 to January 9, 1930
The Detroit Lions, Followed by an unexpected team, the Dallas Cowboys.
Dallas Cowboys
17
Indianapolis Colts
THEE INDIANAPOLIS Colts
12 - Did you know: dallas news.com 10-27-74 to10-5-80
10 years
Yankees 54-62
Currently... The Detroit Red Wings (20 years straight and continuing).
The Cowboys' longest win streak against their NFC East rivals was 10 consecutive games between November 16, 1997 and November 28, 2002.
BYU currently holds the longest home game winning streak in college football with 18 wins
From 1997 through 2002, the Cowboys won 10 straight, and 14 of 15 through 2004.