Everyone seems to love this effect. It's the one I used on the icon I'm posting with, and people always ask me how I do it! So here's a simple tutorial for JUST the effect.
1. Make icon.
2. Open in Jasc Animation Shop 3.
3. Go to Effects -> Insert Image Effect
4. Choose Underwater.
5. Click Customize.
6. Fiddle with it until you get something you like.
7. Click OK.
8. Save icon.
Yay! You're done! If anyone's wondering, these are the settings I use. Please don't make every single icon exactly like this. Same goes with my other tutorial.