From: "Snaggy" < XXXX@XXXXX.COM >
[how to create a broken glass effect]
Here's a procedure that creates a broken mirror effect using Displace and
Stained Glass. These are filters that come with Photoshop.
1) Create an image of roughly the same dimensions as your original
2) add noise
3) Use the stained glass filter to create a pattern whose pieces are the
size of the broken glass you want
4) Save the stained glass pattern as a psd file
5) Click on the image you want to break into pieces
6) Select Filter>Distort>Displace...
7) Set the Horizontal and Vertical scale to 100 - this controls how far the
pieces of glass move
8) Click OK, and see if you like the look - if not, do an undo, and repeat
with a different scale setting
If you prefer not to have the edges of the pieces show so clearly, use
Filter>Other>Maximum to remove the outlines of the stained glass sections
created in step 3.