I think the oddest pistol I've owned would probably be an H&K P7. Whoever designed it unquestionably knew how to think out of the box.
But they do shoot accurately & reliably.
After that, probably a .40 cal Commander Colt Double Eagle, which I happen to wish I still owned. The pistol mucho jammed when I got it, but it responded to tuning and then worked fine. Today it would be worth a lot more than I got when I sold it.
Honorable mention to the XP-100, which arguably is not really a pistol