for my dpns. I always have several dpn projects going. I am usually really good about putting the dpns away when I am done with them. Unfortunately, I was in a hurry one day and didn't put them in the right pocket in my holder. I knitted my size 5 hat with size 7 needles. The dpns all look the same! Sooo, I got out my model paint and painted a stripe around each needle. Now the 5s are blue, the 7s are purple, the 4s are gold, etc. Now I can tell at a glance without looking for my sizer and they are very pretty with the stripes. (Although hubby did want to know why I had 15 needles with purple stripes!
Most of my projects call for the same size needles and it was just easier to have several sets.)