D. an der Brugge and A. Pukhov It is shown that when a few-cycle, relativistically intense, p-polarized laser pulse is obliquely incident on overdense plasma, the surface electrons may form ultrathin, highly compressed layers with a width of a few nanometers. These electron nanobunches emit synchrotron radiation coherently. We ca ... [Phys. Plasmas 17, 033110 (2010)] published Wed Mar 31, 2010.