How to make flickering light? I am working on my animated short, in its first scene I want to make a flickering light(like horror movies) What should I do.
You may achieve this effect fast using Noise Modifier of the Graph Editor. 


Keyframe the lamp's strenght (in my case 1.000) at the desired frame on a timeline with I. Go to the next frame and keyframe it again (light strenght may be the same, since the modifier will do the job).


Go to Graph Editor, press N to open the properties shelf and add a Noise Modifier. Play with its settings for the different results.