I used it today when dropping off my MIL at PDX. It was the difference between making or missing her flight as the "regular" line was very long. I had prepaid her bag fee online.

As another "gadget geek", I couldn't figure out why I had to use the PNR to pull up her reservation, though. I had a bar-coded boarding pass printed at home and the bar code reader seemed to read it. (The laser went off for a moment after scanning the pass.) Nothing occurred on the screen, though.

Therefore, a related question: Has anyone figured out what that scanner is for on the bag tag machines?