Basketball has the BigTen - ACC challenge pitting the conferences against each other.
I would love to see a PacTen - BigTen challenge in football. The rivalry from the Rose Bowl is already there and it could encourage better OOC schedules potentially...not to mention a weekend that could generate a lot of excitement and talk.
Here is how I would set it up:
1) All of the games played the same weekend, perhaps the 3rd week of the season.
2) You would play your opponent for 2 years, once at home and on the road...then they reseed the PacTen - BigTen challenge and give you a new opponent to play again for 2 years.
3) The #1 team in each conference faces each other for 2 years in a row, with the #2's playing each other and so on, all the way down to the #10 teams facing off.
4) Every year the BigTen gets 5 home games and the PacTen gets 5 home games in the challenge.
Just a day dream, won't ever happen.