Was it My Virtual Model, which lets you see a slightly realistic image of yourself at any size? I've only seen it on a few shopping sites, so it lets you see how you would look in various outfits.
www.llbean.com offers it. However, I was thinking that there was a dedicated website that let you make your image without having to go through the shopping hoops to do it. Maybe someone else will know. I'm going to copy this thread to our general chatter forum, and hopefully someone will be able to help