Judge Dredd.
Hmm, how things have changed. I remember well the breakdown of the Lawgiver in one of the early 2000AD annuals. It had a selector lever on the "hump" on the top for the type of ammo, no voice-activation back then. The heat-seeker was a special option that required it to be clipped onto the muzzle from whence it could be propelled by a standard, rocket-propelled, explosive launched round. A bit like a very small rifle grenade, only not explosive in itself and equipped with fins and guidance.
Incidently, terrible pixellation on the camouflage of the gun in the pic. Painted by Pac-Man was it?


