I've had a few but the only one I have at the moment is a .22 LR.
Another .22 I had once looked like all the blue had been removed and a guy who collected then said based on the serial number which had a leading 0, it was one of the ones sold in unfinished kit form and that evidently whoever assembled the kit never got around to having the gun blued. So he had to have it, I guess the kit guns are pretty rare.
Another GW that I had was marked ".357 ATOMIC" which I was told was a short-lived higher pressure .357 Mag.
Also had a .38 S&W GW Derringer made like the Remington. That gun was pretty cool. I think I still have a pic of that one with a tooled leather holster.
Oh, I had a .45 Colt GW that had a Colt barrel installed on it for whatever reason.