Never thought of trying it (wish I had though!!). Post this question under Arts and Crafts too robin - you might get some more ideas!
I am currently wearing a nursing top which would be really easy to replicate - it's a wrap top with a piece of fabric underneath joined at the arm seams and halfway down the side (and looks more attractive without the bump too!). It's very comfy and easy to use; the cream bit is like a crop top and lifts up to allow access IYSWIM. Would be quite easy to make I think.