Tuckerization is the custom of using real people in stories, usually after changing their names slightly (generally in an absurd manner).
This isn't the same as using real-life historical figures in historical fiction, or famous living world figures in contemporary fiction (as J.G. Ballard did). Tuckerization is on a smaller scale and is more concerned with in-jokes (naming a character after one of your friends rather than inventing a name from scratch). The word was derived from the name of writer Wilson Tucker, a regular Tuckerizer.
Cocknobs and Twonkies are often offended when they are Tuckerized.