As they say, easy does it so this is a very easy tweasy tutorial, but the effect that comes out is quite nice. This is what we can get at the end:
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Create a new 500x500 white page.
Filter>Render>Clouds
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Go to Filter>Render>Lightning Effects. Use a setting of 24 or near there. Dont use things like 100 or 1, the effect wont come out, use omni.
Apply a few times using Ctrl-F.
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Then, you are finshed, although you can have a few more additions, such as:
A lens flare:
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Make it into a sig:
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Personally feel that it would make a good webpage background.
More Tutorials: 
