The Little Toe (theory of everything) suggests that the mass of an entire solar system could be converted to energy by a shock wave. And that such a shock wave could start at a planet any where in the system and travel outward at the speed of light.
But some other ideas are still kicking around... http://live.psu.edu/story/13119
and http://www.nasa.gov/home/hqnews/2005/aug/HQ_05229_Swift.html
We see that many GRB have a signature that would match a solar system similar to our own.
