Microplane makes the very best graters for spices, citrus zests, chocolate and other such things. They are the sharpest, easiest to use, and most durable grater of this type that we've come across.
The Master Series Zester is excellent for grating hard spices like cinnamon, dried ginger and turmeric pieces, and nutmeg. It's also excellent for citrus peel, fresh ginger, parmesan cheese and almost anything else. It has the same grating surface as the Master Series Fine Grater but is longer and thinner. Really, it comes down to a matter of preference on the long version vs. the shorter, wider grater.
The Master Series is perhaps the most stylish of all Microplanes, with a handle of Kentucky walnut. This zester is not dishwasher-safe -- hand wash only.