Franklin Armory is selling a single-shot, 12 gauge conversion for the Beretta 92/96 series and Taurus 92 series pistols called the Convert.  According to Franklin Armory, the Convert is available in two models: an AOW (any other weapon) and as a flare launcher.

The Convert replaces the normal slide assembly of the Beretta with a unit that has a tilt-up barrel.  The barrel is aluminum with a steel lining.  There is also an accessory available for the Convert that would allow a shooter to mount the Convert-equipped pistol to the Picatinny rail on a rifle.

Thanks to Cymond for the tip.