I discovered another site from which a few very creative, FREE and potentially useful-for-photo-art
plugins can be downloaded: www.RichardRosenman.com
Click on the button labeled Software, then the one labeled Photoshop. The ones listed first are the more sophisticated offerings, and those are for sale.
Scroll down past them and you'll eventually see the beginning of the complimentary ones. I personally like Grid, Halftone and Pixelate. There are many others from which to choose.
You can't beat the price.