For years I've been using a peg winder attachment for a power screwdriver or drill, I think it was from D'Addario, but not sure. While changing strings last week, the screwdriver fell off my bench and the plastic shaft broke, right at the end of the collet, so time for a replacement. Found one I really like, it has a metal shaft and soft rubber gripper that's small enough it will wind my 12 strings without bumping the peg handle next to it. They also make a crank handle for it so if you don't want a power winder you can use it instead. Here's a picture:
