I have fun with all of the classes I play, but my Swashy will always remain the most fun for me. It's like playing a giant ball of walking doom and destruction. Plus she's infamous amongst the guides on my server.. one of them even got "married" to her (and several others!) for Erollisi Day. :)
Variety is the spice of life though! Been working on my berserker lately, she's lots of fun too, maybe because she can take a beating.
I had originally created her to farm transmute components on Qeynos newbie island (she was level locked at 3 for almost two years and earned slayer of undead/goblin titles there), so I jokingly made her a wood elf with a cute flower in her hair. Changed the hair-do since, but she'll always be a crazy, fragile looking, wood elf.