Low Pixel Photo

This is an easy but fun technique to create a Low Pixel Photo. To Pixelate a Photo just apply the Mosaic Filter: Filter > Pixelate > Mosaic. Just type in any value of Cell size (in this Photo16).
That's it! Easy and Fun.

Another Fun addition to this is the Anaglyph Effect:

Or copy the original Photo and use a Layer Mask to paint some parts of the Original Photo back in. This makes the Pixelation of the Photo like it's a gradual process.