Caught off-guard, I didn't immediately know how to respond. Then, a little self-consciously, I waved back. The hot dog danced in acknowledgement. All around me, other captive drivers beeped their approval. As the light changed and I inched out of sight, I realized I was thinking, "Hmmm...a hot dog sounds pretty good."

As a modernist, I hate to admit that I was swayed by something as irrational as an oversized tube of meat (or meat by-products). But in all honesty, brand characters work pretty well (even on jaded graphic designers). Brand characters help an audience recognize a product and associate it with a fun and engaging personality. Additionally, brand characters are usually cheaper and easier to deal with than real-life celebrities (you can control what the Pillsbury Doughboy does and says in his free time, but not, say, Martha Stewart or Snoop Dogg).

Still, even fictional mascots aren't entirely maintenance- or scandal-free. For example, General Mills has repeatedly tried to change the image of Betty Crocker from "traditional homemaker" to "modern professional," in an attempt to appease feminist critics. More recently brand managers at Procter & Gamble realized that Mr. Clean was reaching an unexpected new target as a gay style icon. (Was it his tight muscle shirt? Or the gold earring?) And even the classic Ronald McDonald needs periodic updates; in the near future, McDonald's plans to recast him as a health-conscious, active sports guru.

Successful brand characters are usually assigned "handlers" who protect them by creating highly detailed behavior guidelines. For example, Planters has decided that Mr. Peanut can never speak—but he can make five approved hand gestures: the wave, the thumbs-up, the hand shake, the hat tip and the hand-out (for product samples). Likewise, the Jolly Green Giant has certain things he can and can't do in the Valley (for example, he can never shake his fist, and he can only wear the red scarf to promote frozen delights).

What makes one brand character more successful than another? According to David Altschul, president and founder of Character, a specialty branding firm, "a successful brand character must have flaws, vulnerabilities and conflict (preferably self-inflicted). Ideally, the character should be connected to the brand in a deep, intrinsic way. And the story of the character should reveal human truths that an audience can relate to."

One brand character who illustrates these attributes is the Maytag repairman, created by the Leo Burnett advertising agency in Chicago. The self-inflicted character conflict is, of course, that the repairman chooses to stay in an unfulfilling job (dependable Maytag machines rarely need repair). The deeper human truth is that the Maytag repairman is lonely—a human condition that many viewers can understand and relate to.

Still, I can't help but feel that Altschul overthinks the whole character issue. After all, a giant hot dog has no mental or interior life, but it's still remarkably successful in rousing cravings for a pre-dinner snack. Furthermore, some of the most successful and well-known brand characters (the Doughboy, Mr. Peanut, the Michelin Man, Elsie the Cow, the Energizer Bunny, the Kool-Aid pitcher, etc.) also have relatively simple personalities—and are often a silent presence. These characters are certainly unique, memorable and relatable...though perhaps not as conflicted as, say, Tony Soprano. In the end, it may be simply too difficult to set up an Oedipal conflict and backstory within a thirty-second spot.