What to do with extra Nagaimo?

I bought some nagaimo,(or mountain yam) for a recipe and I have quite a bit leftover. It's sold here wrapped two or three sections together, so after using about half of one 8" length I've got that one and a whole other 8" section leftover. I did grate more and added some to a meatloaf and a soup, but still that only used about 3 or 4 tablespoons. What else can you do with nagaimo besides grated in things? Can it be cooked like a root veggie? Does it still get gooey when you cook it whole? Any ideas would be appreciated; I'd hate to see it go bad in the fridge. Thanks!