Sea grapes

I have eaten this very special dish for the first time yesterday evening in a small restaurant serving specialities fom Okinawa, the island in the very south of Japan.
It's called umi budo (sea grapes) and it is a delicate, light-green seaweed with small bubbles covering its branches all over. It's scientific name should be Caulepa rentillifera. When you eat it, the bubbles pop nicely in your mouth, leaving a salty sea taste. They are rich in minerals, and I read they can inhibit the growth of cancer and boost immune system.
If you want to know more about Okinawa and this seaweed, go here.