Non-planar graphitic nanostructures have been generated by the reaction of atomic hydrogen with glassy carbon. The process allowed us to generate unconventional graphite-based tree-like deposits protruding from the tips of the etched glassy carbon surface. An individual tree-like deposit has dimensions ranging between 0.5 and 4 mum and is a porous aggregate of polyhedral nanoparticles and curled nanofilaments. Micro-Raman spectroscopy and electron diffraction have been used to monitor the structural modifications induced in the material. The Raman analysis of the bonding arrangement in the tree-like deposits indicates that exclusively sp(2)-coordinated C atoms form these unusual carbon structures.