How we tested
Before testing nutmeg graters, we ran a couple of tests to see if grating fresh nutmeg is worth the effort. We found that in something like a béchamel sauce or eggnog, where there are no other spices to compete with it, fresh-ground nutmeg contributes a distinctively heady flavor that we really like. In baked goods that call for lots of spices, however, such as spice cookies, we found that the signature flavor of fresh-ground nutmeg was lost; ground nutmeg from a jar works just fine in such recipes.
With the holiday season and egg nog in mind, then, we purchased the following: three nutmeg mills, which work just like pepper mills and so keep your fingers completely safe; a new-style grater designed especially to keep your fingers out of harm's way; an old-style nutmeg grater; and a rasp grater for spices.
Only one of the mills produced a neat and even grind in good time. It is pricey, though, at just over $20. The new-style grater does protect your fingers, but it produced painfully little grated nutmeg. To use it, you put a whole nutmeg in a plastic hopper, secure the spring-loaded cap on top, then slide the cap back and forth to grate the nutmeg. The oldest-style nutmeg grater comes in the form of a metal cylinder; the curves are intended to keep your fingertips away from the teeth as you grate. We tested one that cost just $2, but it brought our fingers perilously close to the grating teeth.
The spice rasp grater has, in addition to a comfortable handle, a slender, tightly curled, 5-inch-long grating surface that provides a good margin of safety for your fingertips. It also produced mounds of nutmeg in no time flat and can also be used for grating nuts and chocolate; it's our top choice based on price, ease of use, and output.