The traditional coconut grater used in my home reminds me of metal Japanese oroshigane graters, with their sharp spikes. I have one of these mini metal oroshigane, which was given away free when I bought a piece of fresh wasabi root (see also here) during a Shizuoka prefecture promotion at Isetan supermarket. Identical mini metal oroshigane are available in Daiso too.
Oroshigane come in various shapes and sizes, and in different materials as you can read this article and see in these photos. They are usually used for grating daikon, wasabi, ginger as well as yamaimo/mountain yam for making okonomiyaki, which Lunch in a Box has written about here.
But back to grating coconuts, I was intrigued to learn about the different kinds of coconut graters used in other parts of Asia. There are a few different types from Thailand, a traditional coconut grater stool from Malaysia (I’m told my family used to use this kind too), a version of the stool from Hawaii and this hand crank model from Sri Lanka (watch a video of the suction-base version here).
25/12/07 Update: the South Asian hand crank type with suction base is available at Mustafa for S$6.90. While you are there, you can also pick up a coconut squeezer cloth bag, which feels like T-shirt material (click thumbnails below for larger images).
Coconuts sold in Singapore wet markets today can be purchased either with the hard shell, or without, so you can choose the type that suits your grater. Those that work by hollowing out the flesh from the inside of the hard shell clearly required unshelled coconuts. Then again, you can also just get the coconut stall to use their electric machine to grate the coconut flesh for you!
26/12/07 Update: the suction-base grater doesn’t produce fine enough pieces for getting a good yield of coconut milk (the smaller the grated pieces, the more milk that can be extracted). We had to put the grated coconut into a food processor before squeezing out the milk.