Posts over at PFT about this are pretty hilarious - a lot of mud slinging at the Colts, must be a lot of Baltimore fans over there! Among the claims:

lost games on purpose to get the #1 pick in the draft,
caught pumping fake crowd noise into the stadium,
changed rules league wide to benefit their own team, and
turned off all cold water and cranked up the heat in the visitors locker room during a playoff game knowing the opposition had many players with the flu