In the comments, my statement raised the hackles of several of the always vocal BYB community. They claimed the White Sox are much more hated than the Twins. In their minds, the Black Sox are the Tigers' biggest rival, not the Twinkies.
You can make an argument for either franchise.
With the White Sox, the rivalry goers back decades. You could go all the way back to the Dick McAuliffe - Tommy John fight in 1968, the insanity of 1979's Disco Demolition night, Al Cowens attacking Ed Farmer in 1980, Jerry Hariston breaking up Milt Wilcox's perfect game with two out in the 9th back in 1983, Jack Morris' 1984 no-hitter, and the general surly attitude of your typical Sox fan.
The Tigers - Twins rivalry may not go back as far, but it's been just as eventful. There's the Twins beating the heavily favored Tigers in the 1987 playoffs despite having won 13 less games in the regular season, the numerous horrors which took place in the what was the worst stadium in baseball, the Metrodome (may we all dance on the Baggiedome's grave while waving Homer Hankies), the Twins beating the Tigers for the Central title on the last day of the 2006 season, and of course, the one game playoff already considered to be one of the best games in MLB history, 2009's game 163.
So I'm leaving it up to the BYB community. Which MLB team do you consider the Tigers' most despised rival?