Coulomb's Law
The electrostatic Coulomb force between two particles with different charges and different masses is displayed. Running the simulation shows their subsequent motion. Both the magnitude and sign of charges can be varied as well as the individual mass of each particle. Coulomb's Law QTMovie (144K)

Electric Field on a Test Charge near two Point Charges
Two charges at fixed locations create and Electric Field around them. A positive test charge can be clicked and dragged around to see the electric field that each charge creates at the location of the test charge as well as the total E-field at the location of the test charge. I started to hide the test charge because the E-field has am existence that independent of test charge. You do not need a test charge to create the E-field only to measure the E-fields value at some location. (This simulation will not work with IP versions 3.0 and above because they will not display the zeroth frame correctly. You have to click the run button to see the total E-field vector.)

Charge Particle Orbiting an Infinitely Long Line-Charge
An infinitely long line-charge with a uniform charge density l lies along the z-axis. A charge particle is given an initial velocity in the xy-plane perpendicular to the line-charge. The resulting orbits are very interesting.
Also see Charge Particle Orbiting an Infinitely Long Line-Charge QT Movie (756 K) and Electric Potential of an Infinitely Long Line-Charge Problem

Ideal Conductor
A metal Conductor is simulate with an excess of positive charge. An external charge magnitude can be varied to observe the behavior of the charge on the surface of the conductor.