The shock bolt appearance is controlled by a bunch of game settings - you can change things like color, branch length and frequency, etc. I don't know what mod that person was using, but it probably changed the values of those settings. If you want to pursue it, you should try contacting the original poster of the youtube video.

Not the exact same effect, but, very similar, and lightning-bolt-like, is included in http://www.theelderscrolls.info/?go=dlfile&fileid=219. I suspect you can use just that single ESP file, if you don't want the rest of the changes. (good mod though....)

thanks for the reply ill give it a try