Three encounters for me that I can remember:
#1 at the B18 ORD RCC last December. Can't remember the username, it was 'u6.....'-er-other.
#2 on an HNL-SFO flight on AA in March '07. I was in 2E/F and I saw an FT tagged bag with the person in 2D.
I was taking a picture to show the legroom, then the FT tag appeared...honest!
#3 Today on United 5323 IAD-RIC. I boarded right at the beginning of group 1 and noticed an FT tagged bag waiting to be gate checked. Whoever you are I think you were in 1A...I was schlepping it down the back!