This evening I got home from dinner with friends early enough to sit out on the back deck and enjoy the clouds at dusk. In the south, huge, puffy, mile-high formations traveled from the west toward the lake. Then, as the sun dropped and the magic hour light faded, a massive cloud in the north began to travel across my field of view, also heading east toward Lake Michigan.
This cloud had a light show going on inside it, with flashes of lightning illuminating first one section of the cloud bank and then another. Occasionally, a bolt of lightening could be seen poking out of the cloudy lantern. This light show continued for about ten minutes as the cloud slowly moved from left to right.
I snapped a bunch of photos with the the iPhone camera (using the zoom to close in on the cloud, so the quality is grainy) and despite the shutter lag, I managed to catch a few snaps of the lightning.