Is the speed of light the same as the speed of gravity?
A new more accurate test is being carried out on Sunday to try and confirm whether or not this is true. The results of this potentially have far reaching implications, as this is the fundemental hypothesis for Einstein's general theory of relativity.
One or two sites have reported this, but I noticed it at news.bbc.co.uk/1/hi/sci/tech/2238452.stm