Stablecog is a simple, free & open source tool for creating AI generated images. It uses Stable Diffusion. You can use the default server for free without a sign up, install or predetermined limits. You can also connect to your own server.
As a UX translator for the site, I had the opportunity to test and play with the website in-depth.
I am impressed with the simplicity and ease of use, and the powerful results.
It makes a lot of fun exploring the "lingo" of the algorithm, and see how to yield the best results.
I used prompts in English as well as in German.