As if reality TV weren't soda-saturated enough — American Idol's endless Coke plugs give my colleague Daniel "Party Boy" Coleridge gas — now Pepsi is in on the act. Comic Drew Carey has been tapped to host Pepsi Play For a Billion, a two-hour special airing this fall on the WB. All summer, viewers will check cans of Pepsi, Mountain Dew and Sierra Mist for sweepstakes entry codes, which they'll enter on a website for a chance to appear on the show and win $1 billion.