There is now a free web-based version of Photoshop called Photoshop Express being offered by Adobe on their website. It might provide some photo editing functionality for those of you who don't want to download GIMP and don't feel like shelling out the cash for a full copy of Photoshop. I glanced around the software a bit, and it looks more like Photoshop Elements than a the full Photoshop. I didn't see any sign of layers or any advanced functionality. Still, it's free.
https://www.photoshop.com/express/landing.html