Are you worried that your Soul Gem may be cloudy after the hectic holiday season? Inspired by Puella Magi Madoka Magica, you can now generate your own Soul Gem and try to keep it clear by using the online Soul Gem Maker
The website does not have any overt mention of MadoMagi, nor is it considered to be an officially sanctioned app.
You enter 1. name, 2. Date of birth month and day. Uncheck the bottom box if you do not want your name published in the history. Then click 3 for your own Soul Gem.
My own Soul Gem above reminds me of Homura! It's still clean and clear probably because I have not watched the latest movie yet. You can tweet the image by clicking the button on left or just tweet by clicking the standard Tweet button. Enjoy!