[LibWhacker]

What could “they” be? How about, what could IT be? Something that puts out enough energy in a split second to power the world for centuries. Rather than speculate that vast intelligences, which we do not know exist, are chatting with one another, or trying to chat with us, how about we stick with things that we do know exist and which can generate that much energy... supernovae, colliding neutron stars, etc.? I betcha that’s where the smart money is.

[Nateman]

I'm thinking it's caused by a star in orbit around a neutron or magnastar. Every once in a while a large flare gets near the neutron star and whips around it a few thousand times and then crashes onto the surface of the neutron star. A pound of matter hitting the surface hits with the energy of a hydrogen bomb so I figure the mega tons of charged particles falling In those intense magnetic fields is going to make some very strong radio bursts.