Just something I've always wondered as I never see the winger as the captain.

Wales, Ieuan Evans.

Toshiaki Hirose, the captain for the current Japanese squad for the 2012 Pacific Nations Cup, plays on the wing.

All Blacks. Stu Wilson

Brian Lima of Manu Samoa, captained his team in the later years of his career.

Well Jean DeVilliers is captain of S.A, and he sometimes plays wing. There are no winger captains in super rugby as far as I know.