What moment in One Piece got you Rofl? For me, it was right before the end of Alabasta in the giant bath:

Nami "These guys... Alright, but it will cost you 100,000 beri each."
Everyone "?"
Nami "Happiness Punch!"
Everyone "Ah!"
Vivi "Nami-san!"
Sanji "Mellorine..."

http://img236.imageshack.us/im.../happinesspunch3ns.gif