I wiggle around a lot while knitting. I'll sit with one leg crossed on top, then switch. Lean this way and that. Put my feet up and sit up straight. If I could manage to knit laying down, I'd do it, too!
I'm naturally a fidgeter, and it keeps me from staying hunched in one position too long. I also switch up how I knit. I'll do a few rows holding needles and yarn one way, then change it to something else.