...now with about 1000% less appearance of being hastily slapped together.
It's made of aluminum flashing, some toggle bolts, and washers. Including the tinsnips, I've got about $20 into it. It looks nicer than spraypainted coroplast, too. The bottom opening is only about 1/2 blocked -- I made a full coverage one for winter.
I also got my cruise control installed (the Rostra kit meant for the xB & xA). It took about three hours to do in my driveway, and works great. I'm going to Rochester this weekend, so we'll see how much it helps on the interstate. Even if I have no or negligible mpg gain, it will make long trips much easier.