First, Notre Dame will remain an independent as long as NBC and the BCS continue to make it financially viable for them. Do I think in the long run that this is what both of those parties will do? No. But so far, there have been no signs from either side that the status quo is about to change.
However, if Notre Dame were to ever join the Big Ten, I thought of an interesting alignment that IMO could work:
Big Ten North: Minnesota, Wisconsin, Iowa, Michigan, Michigan State, Notre Dame
Big Ten South: Northwestern, Illinois, Indiana, Purdue, Ohio State, Penn State
There would be on permanent crossover game:
This keeps intact nearly all big rivalries and sets up some great possible championship games in the process. This also keeps travel reasonable for schools in both divisions. Any thoughts on this possible alignment?
Here's how I would see it:
Big Ten "North": Michigan, Michigan State, Ohio State, Wisconsin, Minnesota, Iowa
Big Ten "South": Illinois, Northwestern, Notre Dame, Indiana, Purdue, Penn State
Michigan - Notre Dame
Ohio State - Penn State
Illinois - Iowa
Purdue - Michigan State
Minnesota - Indiana
Wisconsin - Northwestern
Here is my rationale:
I put "North" and "South" in parentheses since the divisions aren't really based on pure geography (which is the same case with the ACC, and for that matter, the NFL which has the Dallas Cowboys in the NFC East), but rather what would preserve the historic matchups along with balancing the power between the divisions.
The critical item at the top that I believe that has to be in place no matter what is that Michigan and Ohio State must be in the same division. There is no way that there can be a possibility that they would play their regular season-ending game and then turn around a week later to play again in the Big Ten championship game. That means that among the 4 "power" schools, Michigan and Ohio State would need to be in one division and Notre Dame and Penn State would be in the other. Michigan - Notre Dame and Ohio State - Penn State are natural crossover rivalries, so that works out well on that front. Illinois - Northwestern, Indiana - Purdue, and Minnesota - Iowa - Wisconsin are all naturally tied together, as well, so they are placed in the same divisions. As a whole, it made more sense to have Notre Dame with its fellow Indiana schools as well as its virtual Chicago market neighbors of Northwestern and Illinois, with Penn State being added on to get an annual ND - PSU divisional game.