I would think that something like a rectangular stole or shawl would work or even a poncho. Not too lacy for privacy of course. Here's a few ideas.
http://www.straw.com/cpy/patterns2/i...ed-poncho.html
http://www.knitlist.com/2003/hugstole.htm
Custom Knits has poncho thing that buttons down the front and has armholes in it which seams ideal to me. Click on view more images and it's in the second group of pix.
http://www.knitpicks.com/Custom+Knits_BD31125.html