My Saturday project...rendering 2D electrostatic configurations. Full resolution: http://i.imgur.com/WluC1.jpg Point charges are all of equal magnitude but mixed polarity, net charge of zero overall. Field "lines" are yellow with brightness increasing logarithmically with field strength. Equipotential lines are blue near the chosen 0V point (at infinity), shading toward red for one polarity and green for the other polarity. The red and green mix with the bright yellow field lines near the charges to make orange and yellow/green. Charge locations are red and black dots to evoke red and blue colors of common DC power supply connections. Scale is arbitrary (could be small charges close together or large charges far apart).