North Berwick: The most fun back 9 in golf?
Pac Dunes: I think it is my favorite course.
Barnbougle: The most fun front 9 in golf?
Rye: Most challenging fun. On top, over, and around dunes, tough par threes, with enough easier holes in between to not make it a slog.
Lawsonia: Big, bold, wild and crazy fun. Come to think about it that might just be Langford and Moreau. I felt the same way about Culver.
For what it's worth I didn't think Tobacco Road was very fun. It was challenging, interesting, and different, but I don't think it was fun.
However, the more I think about it I have trouble thinking of times when I don't have fun when I play golf.
Also, what makes golf fun? It might be width. I agree with Conley Hurst that Sunningdale Old was really fun. I didn't enjoy the new nearly as much. I really think my reason is that I thought the fairways being tight with the very penal heather on Sunningdale New wasn't fun for me.
I think Wide fairways firm fairways where you can swing away with the driver. Big quirky features and or interesting tumbling land and wild greens and a bunch of half par holes equals fun for me.
I also agree with Peter that fun should equal good. These 5 courses are definitely in my list of favorites all time too. Royal Melbourne West, Deal, Sandwich and Pinehurst Number 2 are also in there with my all time favorites but I think they all had a level of difficulty that makes me leave them out of the list for shear fun. What's strange though is I enjoyed playing them a ton and I had fun.
Not to thread jack but, who is the most fun architect? I vote Langford and Moreau for Classic and Doak for Modern. I have a suspicion that Raynor could also be a strong contender for most fun classic, but sadly, I have yet to play a Raynor.