At 7:14a EDT during coverage of the Royal Wedding, FOX News coverage, an aireal shot of the carriage showed many horsemen behind the carriage. A black horse with no rider made its way through the others to the front of the group and proceeded to gallop to the left of the carriage. Camera changed to another shot at this point and I never saw the horse again.
I know how you guys are about the horses :) This was very momentary, much like the pale horse (which I still insist was a reflection) so I thought I'd share it. Perhaps somebody else saw it.