The present inventor devised, among other things, one or more exemplary systems, kits, methods, devices, assemblies, components, and/or software and related graphical interfaces related to signs with interchangeable illumination elements. One exemplary embodiment includes an illuminated sign assembly of two or more alphanumeric lighting elements formed of a transparent or translucent injection- or blow-molded plastic and including a number of surface-mounted light-emitting diodes (LEDs). Each of the alphanumeric elements plugs into power track, and can be independently rotated to a desired orientation relative the power track. In some embodiments, the each of the elements can be wireless controlled or programmed via a smartphone to blink or change colors according to a desired pattern or in response to ambient conditions. In still other embodiments, the lighting elements vertically stack onto a recharge station, and in yet others the elements are powered or recharged via resonant inductive coupling.