|MadSci Network: Physics|
In many books you will read that every electron has the same charge, namely 1.602x10-19 Coulombs. This is, however, not entirely true. The electron charge you find in the books (and above) is valid for a moderately large distance to the electron. If you look very closely, e.g. by smashing electrons on each other in an accelerator, you will notice a gradual increase in the charge. This is, however, an effect that appears only at very high energies, so for `everyday use' the electron charge is constant and the same for every electron.
Hope that helps,
Try the links in the MadSci Library for more information on Physics.