I wanted a knitting project that would go quickly so I made this afghan out of very chunky yarn (acrylic/wool blend). The needles were 15mm. I've never knit with such big needles before, but it certainly made the process go quickly, and it only took about a week of casual knitting to get the afghan finished. I actually found it a bit awkward, though, using the extra large round needle so I probably won't use it too often. Right now I am finishing up a pair of mitts in an angora blend. Angora is just the coziest for cold weather.