I found this December 14, 1998 article that had Olympic and World Cup sponsorship agency ISL proposing a $2.4 billion, 8-year deal ($300M per year) for a playoff. Each school would have been guaranteed at least $1.5M to $4M per year whether it qualified for the playoff or not.
http://findarticles.com/p/articles/m...39/ai_53457348
I didn't look any harder to find a more recent proposal, but if ISL was offering that much nine years ago who knows what might be available now.