Create and Paste Alpha from Transparent Layer; Photoshop Action  

A simple Photoshop action utility for creating a cutout alpha channel from a transparent later in one click!
Will convert any pixel information in a layer to white, add a black background and paste into the alpha channel. Will keep a copy and hide in the RGB channels as well.

Note for this script to work fully you need to first have an alpha channel present. Otherwise it will just create a layer that you can use for alpha channel, or save as unique file.