This deal sounded good, so I went to Target and checked it out. I didn't really believe it was true...
Looked at the mouse aisle and they didn't have any of the MX518. Went to the end of the aisle (toward the back of the store), and they had 5 of them sitting on a shelf, price was still $39.99. I needed a new mouse, so I had picked up a Microsoft Comfort 3000 in case it wasn't on sale.
Took it over to the scanner and it rang up to $29.99. I was a little surprised at the unadvertised sale... thanks OP.