Interchange Weirdness

Today's xkcd got me thinking about the Murfreesboro Road/SR 840 interchange near my house. It's weird in that if you're traveling south on Murfreesboro, you can get on the 840 onramp, stay straight, and end up right back on Murfreesboro Road southbound. Click on the image for a more visual explanation. Here's a Google Earth link as well.