Ask New York-based entertainer Todd Robbins if he has the stomach for show business, and he's apt to eat fire for you, and then follow that by chewing up and ultimately gulping down an entire light bulb.

In fact, he tells PEOPLE.com, "I've swallowed so many light bulbs" that all it would take would be one good attack of flatulence "and I could (pass) a candelabra."

After that, he might also walk on broken glass, shove a series of swords down his throat and hammer a long nail into one of his nostrils.

The only thing that makes Robbins shudder? If anyone calls what he does "tricks."

Whatever they are, Robbins, 45, is displaying them in an awe-inspiring new Off Broadway show that he conceived and in which he stars, "Carnival Knowledge" -- which essentially brings the old circus sideshows of yore (and a current one in Coney Island in Brooklyn) to Manhattan.

"I grew up in suburban South California, and had a nice, normal, middle-class childhood. I hated it," says Robbins.

His escape, starting at age 10, was a local magic shop where old-timers used to hang out and share stories -- and secrets -- with him. When he was 12, a carnival came to town, and its sideshow mesmerized Robbins.

Thus began a lifelong study of the unusual entertainment form that slowly started dying out during the Great Depression and that now he -- after various stints as an actor, a standup comic and even ringmaster of the Big Apple Circus -- has revived.

"I'd like to think I'm paying tribute to the great Melvin Burkhardt," says Robbins of the sideshow veteran who died in 2001 at age 94. Burkhardt, who helped advance the art of the nail in the nostril, was better known as the Human Blockhead.