I agree with the duct tape comments. We once used it, cut into butterfly strips, to close an eyebrow/eyelid laceration. As to difficulty removing it: it pretty much sloughed off when we got to the trail head 2 days later. One of our party was an eye surgeon! He's never seen anything work better, leaving absolutely no scar. We're sold.

Other than that, we're always wearing something that could be cut up for a pressure bandage, etc., if we had to.