When you go to Sagamore Hill — the home (and now museum) that President and Medal of Honor recipient Teddy Roosevelt had on Long Island — you may see a .38-caliber Model 1892 Army and Navy revolver. This was a six-shot revolver chambered in .38 Long Colt.
As a standard revolver, many were produced, but Teddy's gun was important to him. It had been recovered from the wrecked battleship USS Maine (ACR 1). He famously used the revolver to rally the troops (as seen in artwork about the charge up San Juan Hill), but he also pulled the trigger, taking out the enemy with it at least once during that charge.
Roosevelt kept the gun, and after his death in 1919, his house became a museum; the revolver remained in the home for display. It was stolen in 1963 and recovered, but according to a 1990 New York Times article, it was swiped again. Valued at $500,000 at the time, it had not been insured.
Oddly enough, for a revolver that was clearly inscribed "From the Sunken Battle Ship Maine" and "July 1st, 1898, San Juan, Carried and Used by Col. Theodore Roosevelt," it was missing for 16 years until it was turned in to the FBI's Art Crime Team.
The pistol is now back in the Dagamore Hill museum — presumably well-protected against theft. The thief who took the gun in 1990, though, is still at large.
Below is a video by Brad Meltzer about the gun's history — and its 1990 theft.