I've always love crystallized ginger. It's everything good about ginger, but the added sugar rounds out the flavor and tames it, making it less aggressive. I love ginger, but sometimes it tastes a bit like mace - the personal defense product, not the spice - and its flavor is so clean and razor sharp that sometimes it cuts through other flavors no matter how little you use. But by adding sugar to it, crystallized ginger rounds out those sharp edges and gives it more depth. As cinnamon is to red hots, so is ginger to crystallized ginger.
People use crystallized ginger in everything from chicken salad to desserts and it goes especially well with sweet potatoes (an early version of the Sweet Potato Puffs I did featured crystallized ginger). Right now, however, I'm only using it for one thing: the pear and fennel compote for the Portobello Mousse.
I really wanted to get the taste of ginger into the compote but adding one more wet ingredient was going to wreck its consistency and turn it into a runny mess. Chopped, crystallized ginger turned out to be a perfect solution, because it also added another texture to the compote. No one notices it's there when they eat it, but it's what makes the pear and fennel (or peach and fennel in summer) compote taste so right.