I absolutely am a big fan of One Piece. 4kids pretty much [tornado fang]'d the Western audience, but lucky for me I downloaded the serie and started watching in 2005, and have been watching whenever it gets updated.
One Piece always make me laugh through EVERY episode. Seriously, always 1 little humor scene can be found for me. Next to that, it has a gigantic cast of interesting characters and background, both of them still growing stronger. The plot is just great, with huge epic arcs awaiting viewers.
It also has lots of delicious villains with their trade mark laughs, great music during the episodes as well as openings plus some endings, and good, and I mean good fighting scenes. You never know for sure how an enemy can attack the Straw Hat Pirates. Lastly, One Piece is an original pirate story, how cool is that!?
I will definitely continue watching the serie!