I've seen a couple places in Bryyo where if you shoot the fuel when it's close enough to your face, it will show Samus's Face (reflection). I also believe that if you stand near a wall and keep shooting it, you can also see Samus's Reflection.
I believe that there is also a couple reflective spots on the SkyTown planet as well (forgive me for not knowing it's exact name, it's been several months)