Is there gravatar for user namses?
Alternative for Gravatar which supports SHA256
Why is my gravatar size inconsistent?
how to tell if a url is for default blue image gravatar
Web service or library to generate colored boxes with first letter of user's name (like in Gmail Android/iPhone) app
Google account image from email
How to get images using Gravatar image requests
Is there a Gravatar signup link to pre-populate the user's email address?
What is the system that allows for anonymous pictures portraits?
How to generate the random default “gravatars” like on Stack Overflow? [duplicate]
how do I change the gravatar RoR plugin to use d=identicon?