Here is an interesting nugget from the Reno News Journal: Before he agreed to serve as a coaching consultant for the Kansas City Chiefs, Chris Ault weighed interest from both the Green Bay Packers and Minnesota Vikings.
As you might know, Ault is the former Nevada coach who is credited with designing and popularizing the "Pistol" offense that reached the NFL mainstream last season. (He was the college coach of current San Francisco 49ers quarterback Colin Kaepernick.) Ault told the News Journal that he isn't sure whether the Chiefs want him to teach the Pistol to their offense or coach up their defense on how to stop it, and it's fair to wonder the same for the Packers and Vikings.
In the Pistol, the quarterback lines up in a modified shotgun formation, usually closer to the line of scrimmage than the traditional shotgun, with a single running back lined up directly behind him. It prevents defenses from keying a side and provides the quarterback a head start on running if the alignment allows it.
The Packers were blown out of the playoffs by Kaepernick and the 49ers, sending them into an offseason dedicated to stopping the read option scheme that the Pistol provides for. Would the Packers want to run a version of the Pistol with Aaron Rodgers at quarterback? I'm not sure about that, but there is no doubt their defense could use the tutoring. The Vikings, on the other hand, have a similarly athletic and less accomplished passer at quarterback in Christian Ponder. It wouldn't be outrageous to see them dabble in the Pistol with Ponder or perhaps even Joe Webb this season.
Finally, it should be noted that Ault shares an agent (Bob LaMonte) with Vikings coach Leslie Frazier. LaMonte also represents Packers quarterbacks coach Ben McAdoo. Sometimes those affiliations are notable when it comes to the rumor mill.