Can a charge smaller than that of an electron exist? If so how?
Dipole moments have a distance times an implicit charge, but you could give the moment as unit charge separation times a distance which is not the bond length. This would eliminate fractional charges and suggest some distance, which suggests that an electron and the nucleus are point charges separated by something less than the bond length. This is difficult to visualize. The electron is not really a point charge. Dipole moment is not separable into fractional charges or tiny distances, it measures a distortion of charge.
And when you think about it, an undistorted charge distribution (like electron density in benzene) is still &quot;distorted&quot; in that electron density is between atoms and above/below the atomic plane.
Other fractional charges might be imagined in compounds like magnetite: $\ce{Fe3O4}$. Each iron has a charge of $\pu{2.666}$. But if you describe magnetite as $\ce{Fe2O3.FeO}$, then two thirds of the iron atoms have a charge of +3, and one third have a charge of +2. More satisfying.
And then there is cyclopentadienyl anion:

where each carbon has an extra 0.2 extra electronic charge, and there are other ions like cycloheptatrienyl cation, cyclopropenium cation, etc. that have a surplus or deficiency of electrons.
But there is no fractional electric charge, just fractional molecules, or combined valences. Although, I still wonder how quarks can have a partial charge!