I would need a time period and possibly a team to answer this better. Here is a current list:
These quarterbacks have worn the number 6 for the Pittsburgh Steelers:
* Bubby Brister (86-92)
Jay Cutler wears number 6.
and Jason Street
Most recently, backup quarterback Brian Hoyer wore number 6 in the 2012 season, in which he only started one game.
sonny 6 killer
Bubby Brister.
QB Jay Cutler
That was Pete Gonzalez, a backup in 1998 and 1999 for the Steelers.
Bubby Brister
Kordell Stewart
Steelers starting quarterback Ben Roethlisberger wears #7.
Ernie Pough wore number 22 in 1976 for the Pittsburgh Steelers.
There was no player on the Steelers that wore the number 8 in 1975.
In 2010, no Steelers player wore #39.
In 2011, no Steelers player wore #8.
Willie Reid wore number 15 for the Steelers in 2007.
Erric Pegram wore number 20 for the Steelers in 1995 and 1996.
In 1995, Damon Mays wore the #86 for the Steelers.
Cornerback Chad Scott wore #30 for the Steelers in 2000.