Another way to make it rain. Find a nice picture of water drops. Neutralize it and add it to a new layer over your image.
Save this file as a PSD. call it Drops (or whatever).
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Then turn off the water layer and click on the background image.
Now go to Filter/Distort/Displace
Apply these settings.

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Click OK and select the PSD that you just saved (Drops)
It should look like this.
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Now activate the water layer and set it to soft light, or overlay.
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There ya go.

I know the easiest way of all.....spit on the screen.. ..of coarse saving is a bitch.. .but it's very realistic.

Dang Rey! A while back we had a contest where I wanted to make a "sneezed on" screen. I coulda used the technique you just outlined.

WHERE THE HELL WERE YOU A FEW YEARS AGO WHEN I NEEDED YOU!?!?

looks at REY's water....looks at tofu.....looks back at Rey's water..... ...dude a sneeze like that could dehydrate ya.

Allergies.

Use screen capture...duh.

Bumped for JC

great tutorial reyrey, thanks

What means "Neutralize"?

Desaturate? Make into BW? I'm lost.

I'm almost positive it was a typo.
ReyRey probably meant 'neuter'

Sorry. Yes, Desaturate. I'm talking press terms. Oops.