Colt Lightweight Commander Rail Gun
I believe this was in 9mm , but not sure.
...and in .30-30 and .500 S&W. Took these for a co-worker who was talking about getting a S&W .500, because he thought it would be the most outrageous handgun.
Whether it's the best solution for carrying such a handgun concealed, would probably be a personal decision.
I confess, I've had a hankering for one of these S&W Performance Center Model 629s. That snub barrel will hardly get the most effective performance out of any .44 Magnum or even .44 Special round, but it would be a far better solution for carrying on most environments. (My opinion.)
All stainless, so the weight would make it easier to shoot than the lightweight versions that use a lot of alloys.
Granted, it's fat enough to make it harder to conceal.