Greg Ossmann is surrounded by signatures. Tens of thousands of 'em. The assembled autographs of baseball luminaries. Political figures. Historical legends. And the pop celebrity John Hancocks from half of Hollywood, it seems.

"I have one of the largest private autograph collections in America," is Ossmann's assessment of his immense treasure trove, which includes 50,000 photos, primarily of 20th-century American icons.

Ossmann, the director of public affairs at Mercy Hospital Fairfield, is candid about his one-of-a-kind collection: It's an obsession.

"I got to thinking, my dad was a CPA and did a lot of work for the Yankees," says the amiable executive, when asked about the origins of his hobby. "I was constantly around the Mickey Mantles of the world, but never got an autograph." Now he's the owner of a Babe Ruth baseball, among other trinkets.

"I am by nature a packrat," says Ossmann, who always finds himself off on adventures to flea markets and such in search of a bit of Americana. "A sense of history is a good thing to have."

That it's a hot investment goes without saying. "It beats the market, that's for sure. Every time somebody dies, the value of the collection goes up."

Ossmann estimates his hobby weighs in at $5 million, based on current eBay prices. "I recently bought 24 photos for $800," he says. He turned around and sold one of those photos, of Marilyn Monroe, for $18,000.

In the world of fleeting emails and electronic communication, there's something permanent about an autograph. President Franklin Delano Roosevelt is perhaps the world's most famous autograph collector, but hundreds of thousands of people — from star-struck teen-agers to savvy investors — have pursued this pastime.

Included in the Ossmann archives? An Eric Clapton guitar, a scrawl by President John F. Kennedy, and the signatures of pop culture icons such as Michael Jackson, Joey Bishop and Mick Jagger, political figures such as Admiral Stockdale (remember Ross Perot's running mate?) and — of course - name your baseball hero. How does it feel for Ossmann to find himself housed in a home, paired with all these famous faces? "My life is like Forrest Gump!" he jokes.

Some collectors might hoard routine correspondence, handwritten letters, manuscripts, inscribed books or even canceled checks. Ossmann likens it to holding a piece of history in your hands.

He describes himself as a cataloguer — "I love to catalog things." Friends and family even ask the former Lockheed Martin and Milacron executive, "They say, 'Why don't you create some sort of museum?' "

"The whole cult of celebrity fascinates me," observes Ossmann, who is quick to stress he is a passive collector. "I don't stalk people with a camera."

Sometimes, collecting a signed photo is as simple as writing the actor or singer, or more likely, their secretary, agent or fan club president.

"The thing that matters the most to me is my JFK photo, signed for a Kentucky legislator."

That, or "if I inspire some kid to find a passion."