I've seen some recently, mostly .22/.410 or .22/20 ga., but I also saw a .30-06 over .30-06. I know that you can have either gunsmiths or company's custom make you one in any caliber/gauge combo you want, but you'll pay for it. A buddy of mine has a .222 over 20ga made by savage, but it's from the 1890's I think, before they closed down for a while, so I'm REALLY doubting they still put that one out. I've only ever seen one other that was a .30-06 over 12 ga, a pawn shop wanted $3000 for it, so I couldn't get a hold of it, but it didn't sit in there very long!!!!!