This one is for the Glamor Shots people. We are going to take a picture of a model and soften up the image in a fuzzy kind of way, but still keep sharp detail.
Begin with your picture.
Switch to the channels palette and choose the red channel.
cmd/ctrl+click on the channel thumbnail to load the highlights
Click on "rgb" to show all channels
Switch to the layers palette
Press Cmd/Ctrl+J to copy the selection to a new layer (or click layer via copy)
Select the new layer by cmd/ctrl+clicking on the thumbnail Fill with white.
Add a 7.9 pixel Gaussian blur.
Finally, switch to Luminosity mode and drop to opacity down until it looks oooh sooo sweet. In this case 60% works a treat!
Have fun with this technique.