You guys might remember a few months ago, the scientists at OPERA announced that they found an apparent discrepancy between the measured speed of neutrinos and the expected speed (close to the speed of light).
Looks like they found the reason. Apparently, a signal delay the size of the discrepancy was created by a bad cable connection. :-) I have to say, that has to be one of the more embarrassing possibilities for a systematic error.
http://www.theregister.co.uk/2012/02..._opera_result/