Sorry, no plans for a Windows app in the foreseeable future. See
this post from our CEO for some of the reasoning behind that. (Please don't interpret my brevity as disapproval, btw. It's a totally reasonable/understandable request! I just can't can't think of anything to say that Ken doesn't say better in that post.)
We have discussed a Web app; our current projects have us too busy to work on one for the time being. Maybe someday - the amount of demand for one is pretty apparent to us. :-)