@mokha: There are a number of website you can watch one piece episodes for free.
Funimation simulcasts One Piece
Also, for future reference if you are looking for all anime that are available online via legal streaming services, this unofficial list is very helpful.
Please don't post pirate site on here
Yeah, there is One Piece Official
@Destinyheroknight: Fixed his post (removed site in question).
Well, try hulu or search Google
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