Alright, this is an annoyingly simple trick to make lots of little stars (for use with some night scene, perhaps). All you need is Photoshop 7.0 onwards.
(Note: In this example, I will be using solid, plain background for the stars. Feel free to load with whatever thing you need to add the stars on. Or you gan use Google Image with the keyword ‘Night Sky’, hehe)

First, Make a new layer on top of the background layer you’re working on, and fill it with gradient (from white to transparent) (see figure) .

Then, set the opacity of the top layer into 5% (or less). Don’t worry if you can’t see the layer anymore. It is meant to be like that.

Now here’s the main trick - set the top layer’s blending mode to ‘Dissolve‘…

… and you should be seeing star-like patterns to appear!

The amount of stars might be a little too much or too little for your liking. Play around with the ‘opacity‘ and ‘fill‘ amount (see figure below) until the amount of ‘Stars’ fits your needs. I’ve placed a night sky in the example below just to show how its like.
It probably doesn’t look too realistic, however, you don’t complain much on a 10-second job!
Have fun :D
