Faded Gray Tutorial
From This 
To This:
In 8 Steps using Photoshop CS (might be translatable to other graphics programs, no filters used)
1. Take your base image and crop/resize it down to 100x100
2. Duplicate the layer (Ctrl+J) and apply Filter>Sharpen>Sharpen. Blending Option: Soft Light
3. Select All and go to Edit>Copy Merged (Ctrl+Shift+C) and Paste as the Top Most Layer.
4. Desaturate the layer made in Step 3 (Ctrl+Shift+U) and Blending Option set to Darken.
((For this icon, I took the eraser tool and erased Usagi's eye out of the topmost layer so her eye was nice and blue, this is Optional))
5. Now for textures! Take the below texture by lil_brokenangel @ LJ and paste over the top with a Blending Option of Lighten
6. Take the below texture by lil_brokenangel @ LJ and paste it to the top with a Blending Option of Lighten also
7. For the border, I selected a 2px wide border and filled it in with black
8. Now set that border layer to Blending Option: Overlay
To This:
In 8 Steps using Photoshop CS (might be translatable to other graphics programs, no filters used)
1. Take your base image and crop/resize it down to 100x100
2. Duplicate the layer (Ctrl+J) and apply Filter>Sharpen>Sharpen. Blending Option: Soft Light
3. Select All and go to Edit>Copy Merged (Ctrl+Shift+C) and Paste as the Top Most Layer.
4. Desaturate the layer made in Step 3 (Ctrl+Shift+U) and Blending Option set to Darken.
((For this icon, I took the eraser tool and erased Usagi's eye out of the topmost layer so her eye was nice and blue, this is Optional))
5. Now for textures! Take the below texture by lil_brokenangel @ LJ and paste over the top with a Blending Option of Lighten
6. Take the below texture by lil_brokenangel @ LJ and paste it to the top with a Blending Option of Lighten also
7. For the border, I selected a 2px wide border and filled it in with black
8. Now set that border layer to Blending Option: Overlay