Today's Wall Street Journal reports on a new advertising trend: "The most obvious alternative to TV clutter, placing products within shows, is generating some backlash among viewers. Marketers and media buyers see the 'situ-mercial' as a promising alternative." What is a situ-mercial? It's a commercial designed to look, sound and feel just like the show it's interrupting. For example, a car insurance commercial set in a jail cell is airing during court shows and dramas.