This effect throws snowflakes over your image:
Though snowflakes are normally white you can change the color at will. If the color is not set to white then the variability slider changes how much the colors of the snowflakes can vary.
You can select if the snowflakes are distributed randomly over the image or according to the light or dark parts of the image. Why would you want to be able to choose this? Well it means that you can write with snowflakes:
To get the above effect you start with an image like this:
...bring it into Repligator, select the Snowflakes effect and set the dialog to the settings you see above.
A related effect is the Sparkles effect.
