All of them are convinced they've deciphered the script of the Indus Valley Civilisation, a blend of signs and symbols. "They claim they've solved it and that the 'case is closed'," says Mr Rao ...

Well, not very much. Indus Valley writing used at least 400 picture-signs - they were not letters like in our alphabet. But the longest bit of writing found has only 26 characters. No one knows ...