About 15 years ago, I'm on a business trip, walking down the street in NY city. This excited guy runs up to me, and says he's so glad to meet me in person. "I have your DVD!!!," he tells me. And that's how I learned I was in porn.
"Really?," I said, hiding my total confusion. "Which one?" I did learn the name of the studio from him, and later found myself in a San Francisco hotel about a block from their offices, so I paid them a visit. They were glad to see me, too, and gave me a big stack of DVD titles in which I appeared. More like a fire-hose, not a leak...
Later, I did some real porn now and then, with full consent and contract. That "leaks" in a way, too, when it gets pirated on one of the "tube" sites, and suddenly all your friends notice it. It's weird to walk into a party, and have the bartender say "I was just jerking off to you fucking that twink. What can I get you, sir?"