Technique #2. Displacement Mapping to a Layer Mask
Here's a variation on applying one of the typical filters, courtesy of photographer and Photoshop educator Eddie Tapp. Eddie shared his technique with me at Photoshop World, and with his permission I've included my slightly adapted version here. The key is using the Displace filter and some of the textures that are built into Photoshop.
Press Command-J (PC: Control-J) to duplicate the Background layer.
From the Image menu, choose Canvas Size (or press Command-Option-C [PC: Control-Alt-C]). In the Canvas Size dialog, make sure the Relative checkbox is turned on and enter 1 inch in both the Width and Height fields.
Press-and-hold the Command key (PC: Control key) and click on the Create a New Layer icon at the bottom of the Layers palette to create a new layer below the current layer. Press D to set your Foreground and Background to the default colors. Then press Command-Delete (PC: Control-Backspace) to fill the new layer with white.
Press-and-hold the Command key (PC: Control key) and click on the top layer's thumbnail (the copied Background layer) to load it as a selection. Make sure that the top layer is active and click on the Add Layer Mask icon at the bottom of the Layers palette to create a layer mask from your selection.
With the layer mask selected, from the Filter menu, choose Distort>Displace. This filter needs lots of experimentation, but to start off, in the Displace dialog, try using numbers from 1020 for Horizontal and Vertical Scale. Click OK, then in the resulting Open dialog, you'll choose the displacement map to use with the filter. You can find a series of built-in textures that you can use as a displacement map on a Mac in Hard Drive:Applications:Adobe Photoshop CS2:Presets:Textures, or in Windows in C:\Program Files\Adobe\Adobe Photoshop CS2\Presets\Textures. In this example, I used the Frosted Glass texture.
As a result, the layer mask looks like the capture you see here.
The goodies CD that ships with Photoshop includes additional textures that you can load and use as displacement maps.
You can also get some interesting effects by applying the Displace filter again using different settings and a different displacement map, and then using the Fade command. Here I chose Lines as the displacement map, then chose Edit>Fade Displace, and then lowered the Opacity to 40%.
Here's the result of using the Fade command with the Opacity set to 60% and Mode set to Hard Light.
Variation 1 : Fade with Hard Light blend mode
Here I added an inner glow by clicking on the Add a Layer Style icon at the bottom of the Layers palette and choosing Inner Glow from the pop-up menu. Then I sampled a color from the image by clicking on the color swatch in the bottom left of the Structure section of the Layer Style dialog, and increased the Size to 25 pixels in the Elements section.
Variation 2: Inner Glow
In this example, using the Elliptical Marquee tool (press Shift-M until it comes up), I created a feathered selection, and then created a layer mask from the selection. I then applied the Displace filter using the Frosted Glass texture.