benzene does not conduct electricity, because the electrons have no way to "hop" from molecule to molecule, and it isn't charged by itself to induce ion flow.
The conductivity of pi-conjugated systems (such as buckeyball and nanotubes) lies indeed in the way that the electrons are delocalized within the molecule and thus you can have electrical flow. As those (buckyball and nanotube) are in essence one large molecule, they conduct electricity along the molecule.