Over the past year, momentum has been slowly building for the NFL to establish a developmental football league. It's now looking like we could see such a league in the near future. The last minor league the NFL had was NFL Europa, which folded in 2007 due to funding and economic issues.
It was a good idea, but poorly executed when considering it was overseas. Since NFL Europe folded in 2007, the NFL has been the only one of the four major pro leagues to not have a developmental or minor league system.
A minor league in and/or around NFL cities would likely draw bigger crowds and more interest. Theses games would theoretically consist of practice squad players and free agents looking for work.
SB Nation's Jeff Gray examined the case for a developmental league, and how it would enhance the NFL.
Personally, I love the idea, and I would watch every game that had Bengals practice squad players on it, just to get a better feel of what they might be capable of at the NFL level.