The Zend Developer Zone has come across an interesting face about the SourceForge website - it uses the Zend Framework to add OpenID functionality to its pages.
According to the press release from SF about their OpenID support:
OpenID is getting tremendous traction and we're happy to be jumping into it. it's bringing us back in touch with fresh web (2.0) technology. [...] We've spent the past couple weeks on it - integrating the Zend Framework OpenID component into our site code. we like the framework as a whole and I personally hope to use more of it in the future.
There might be a few kinks in the process, so if you're seeing issues with your OpenID working on their site, check out the FAQ they've posted to help.