I think it's a good idea. The problem, however, is that once you've peed through it, what do you do with it? I wouldn't want to put that back in my purse without cleaning it thoroughly, and I can't imagine trotting up to the sink and washing it in front of people. Thoughts?

Edited to say: Oh, I see there is a plastic bag. I dunno. I think I'd have trouble carrying it around after it was used. They should make disposable ones out of waxed cardboard you can just throw away. Although I suppose that isn't environmentally conscious...