To animate light like that you'd use Adobe Imageready and create an animated gif. Basically you'd need layers for each possible frame that would exist and then you turn them on or off for each frame and tell it how long to leave each frame on screen for.
It's how I make all this kind of stuff:



If you want to go really crazy, Adobe After Effects has a lightning plug-in. It doesn't look much like real lightning, but it certainly looks as much like lightning as the stuff shown in this thread - and it's much more malleable.