001.
Duplicate your base and set it to screen at 100% opacity.
The number of duplicates and the opacities obviously depend on your base.
Just make sure its a little overly-bright to start with.
You can always go back and fiddle later.
Sharpen if needed.



002.
Create a new layer and fill it with (#407E90).
Set it to softlight at 100%.


003.
Create a new hue/saturation adjustment layer.
Increase the saturation to +82.
Again, the settings depend on your base.
My base was pretty dull, so a high saturation worked.

Set this layer to softlight at 100%.
I still wanted it a little more vibrant, so I duplicated the layer and lowered the opacity to 30%.


The following steps are where it gets a tiny bit tricky. You just have to pay attention to what you are doing.

004.
Go to.....
Select >> Select All.
Edit >> Copy Merge >> Paste.

Make sure the new layer you get after this step is on top.
If you are satisfyed with the look, go ahead and flatten.
If not, go back to your layers and do your tweaking.

Once you have your new base, its time to blur, crop, add textures, etc.

005.
With the eliptical marquee tool, select an area of your icon that you do NOT wish to be blurred.
Go to...
Layer >> New Layer >> From Copy.

Once you have your selection as a layer, select your base layer.
Radial blurs really work with this type of icon, and helps the main focus point stand out more.

Go to...
Filer >> Blur >> Radial Blur.

Use whatever settings you're comfortable with.
I used amount +30.


006.
Take the top layer (your unblurred selection) and duplicate it.
Move it slightly in any direction that you'd like, and lower the opacity to about 40%.
Erase any parts of it that cover the original layer.


007.
Finally, just choose any grungish texture to finish off with.
I chose one by blimey_icons.
Set it to multiply at 100%.

Final Product



Other Examples (With slight variations)
 

Any questions, feel free to ask.