I have some Injinji's that are very thin, and some others that are about medium weight. They are damn pricey, though, and IMHO your toes will not stay as warm as they would in regular socks.
I wear regular "no-show" socks (Hanes I think) that just barely come up past my heel, with my Stem Primal Origins, and have no problems with natural foot movement as compared to when I wear them without socks.