Due to a bunch of gear purchases, I now have 3 of the same all-in-one D'Addario winder tools. I just restrung my 12 string acoustic with one and, wow, I was missing out! That saved me so much time!
i got a string winder cordless drill bit attachment recently & it rules. i really hate changing strings, but using that thing really cuts down on the time it takes. it's super easy to way over tighten the strings, though! gotta be gentle with the drill.