I think I'd like to have a .22 Diamondback with the 2.5" barrel, just to make a complete set with my 4" and 6".
Second choice would be a post-1972 Colt Dick Spec, to screw the 3" barrel I bought from Numrich 20 years ago onto.
Third choice would be a nice postwar but pre-Mark IV Colt Government Model in .45, or even .38 Super. I'm this close to getting a reasonable facsimile together from parts, but an original would be better.
I'd also like an old Colt 1911 in .38 Super. And it's been double-digit years since I've seen it, but didn't Burt Reynolds also pack a 4" Diamondback in "Sharky's Machine"? I seem to recall the line "...it bites".