 What have you changed your mind about recently?
xayide: Seat belt laws.  
For years, my inner Libertarian would cringe at the idea that the government could force someone to do something they didn't want to when it was their own life at risk.  But then my inner Republican realized that if I were to be at fault in an accident, I would be financially and possibly criminally liable for a much steeper offense if the other party wasn't buckled up.