This was something lurking for some time in the website back-end but was never enabled on the site. I decided to take this feature live.
If you go to your manage page, you can now choose a generated creature for your image other than a robot:
Just for fun - some examples:
Of course, you can still upload your own images too.
Nice feature, generated some good ones!
But it also was kinda cool before, when you had to have luck to get a good profile pic :)