My son sat next to the world's worst tourist on a flight from Sydney to Denpasar, Indonesia. His seatmate nursed a bottle of sizzurp -- a potent mix of codeine and Sprite -- and the man twitched uncontrollably for the seven-hour flight to Bali. When the intoxicated tourist disembarked on the conservative Hindu island, he collapsed on the terminal floor. The last time I saw him, customs officials were trying in vain to revive him from an opiate-induced stupor.