Chic bandana wrapped around one side of your head?

Pirate patch?

Designer duct tape?

Hope you didn't mind a little levity - my DH seriously considered #2 when he had to drive 15 miles at night when commuting home in the dark. It beat keeping one eye shut. But someone on this board or another we frequent pointed out that if you use glasses and put something opaque on the offending eye's lens, you will then still have some peripheral vision in the case that some driver off to that side does something unexpected - you'll still be able to see the movement and react, in other words.