I've made an entire working language (more of a code, really, but language sounds cool) based on circular Gallifreyan in Doctor Who. It has a real structure, but I'm not going to give that away.
This one says 'sonic screwdriver'. I made the stupid mistake of drawing it on the back of another one, and it's all bumpy and lousy. Don't judge me. I need to save space...
Let me know what you think! And don't be too harsh.
Disclaimer: I do not own Doctor Who, BBC does. Please don't sue me, I love you.