Git Reports is a free service that lets you set up a stable URL for anonymous users to submit bugs and other Issues to your GitHub repositories, without exposing your code, requiring users to log in with GitHub, or using a messy two-repository solution. It works with public and private repositories, and it works with personal and organization repositories. It's super easy to set up: log in, allow access, and activate your repository from the list! Check out the tutorial for more details.
Free and ad-free! This service is the side project of a broke college student, so if you like it, throw me a few dollars.
Made with love by Zach Schneider. I'll be graduating in May with my CS degree, so if your company needs Rails developers, check out my résumé.
The GitHub API doesn't have a whole lot of scope options; unfortunately, in order to get write access to a repo's issues, I also have to request write access to the full repo. The site's open-source, though, so you can check it out for yourself or even self-host your own copy if that's your thing.
Dogfood it with a bug report here, or you can just create a new issue on GitHub; the repo's public. Feel free to send a pull request if you fix a bug or add a new feature.