Originally Posted by 2bet

Make your images very SE friend (example, site.com/keyword.jpg) - you can place them in a folder of course, but keep it very short simple urls. Use proper Alt tags for your images. Remember, Google can not see your images, they can only read the image name, its location and the Alt tag describing it. Your text around the image that is related to the images helps, but this is based on our testing.

If your image is a naked girl and you name it Naked-Girl.jpg, your up against alot of very aged pictures and its going to be hard to rank for that, but naming the image Naked-Girl-Giving-Blowjob.jpg (assuming thats what the pic is) has alot better shot