  Motivated by the results of recent photoemission and tunneling studies, we
discuss potential many-body sources of a finite gap in the Dirac fermion
spectrum of graphene. Specifically, we focus on the putative Peierls- and
Cooper-like pairing instabilities which can be driven by sufficiently strong
Coulomb and electron-phonon interactions, respectively. Our results compare
favorably with the available experimental and Monte Carlo data.
