I was hoping someone could shed some light on this for me. I only recently acquired the GOTY edition of Borderlands 2. In the Hammerlock DLC, sometimes I'll stumble upon a switch on the ground that when activated, creates an impenetrable barrier like the Angelic Guard loader does. You then have to smash the switch to make the barrier go away. I think I also saw progress toward a certain badass challenge or something, but I was too busy fighting the natives to really pay attention.
So what's the deal with them? Are they part of some unmarked quest?