I'm a bit late to the game, but early last week I made a new account on a website called "artbreeder," and I started manipulating photographs of people I uploaded onto the internet. You get up to three a month (if I understand the terms correctly), and if you want more than that...well, you can pay a monthly subscription and it allows you to work on hundreds. I think it also speeds up the time your "seed" image takes to upload to the site. Mine usually take a few hours. So, I usually would just upload something before bed. When I woke up in the morning, I was able to play around with it as much as I liked.
Artbreeder's results are startlingly good. I'm also shocked at how quickly I can make an image of a fictional person that doesn't even resemble the original seed. In the manipulation of the photos, you have sliders. Just to name a few, there is gender, hair color, eye color, width, yaw, and pitch. These last two...the ones called "yaw" and "pitch," actually blew my mind. "Yaw" allows you to turn a person in a photograph in real time. And I can't tell that the original photo wasn't turned that way. To explain it further, let's say a person is staring off to the left in a photo, and you want to see what they look like straight on. You can do that by adjust the "yaw" slider. They turn right in front of your eyes until they are straight on and staring at you in the picture.
"Pitch" does the same thing, only it raises and lowers the head. Too much pitch in one direction will have your photo staring at the sky. The other way has them looking at the ground. There are sliders for the shape of the eyes, for changing the emotion, for making a person smile in a photo or frown or just like like they are holding back on something. Here's some samples of what you can do in this weird (and free) program and by the way, none of these people exist in real life to my knowledge: