The very first implementation of GalaxyMage used some terrible isometric art... but I couldn't get it working right, which is what caused me to explore OpenGL. Never looked back... :)
A demo map containing a castle. Shows OpenGL lighting, colored map squares, and menus.
Castle with night lighting and a "fire" lit inside. Lighting is set on a per-scenario basis, so the same map can be used for battles in the day or at night.