Yes! What a nice gift! I bought two on ebay. They are really just moss/algae balls that live in my tank and absorb extra nutrients- nice for keeping algae down and my fish seem to not eat them. I like an asian theme for my tanks so thought they were a nice touch.
These things are so neat. They are an endangered species in the wild, not because of overharvesting, but because there is only one lake (I think) that they inhabit in Japan. There are also European versions, though they aren't as well known.
They are hugely popular in Japan. They require little care other than periodic turning (and that's only if you want them to grow spherical), some fertilizer (unless they're in with fish, which will fertilize them) and light.
Thanks guys. Dropped it my Discus tank... got a slight algae problem in that tank anyway, maybe the moss ball will help a little. I also hear Marimo balls are supposed to bring good luck... we''ll see what happens.