I have been pondering about this for a few days, and I'm surprised this hasn't been done yet or isn't very popular.
What I would like to see was a way to run a PHP application inside a desktop application. For example, the application would need its own mini webserver that doesn't handle requests, but allows PHP to be run.
Sometimes I have been set with tasks that clients demand coded in C# or .NET, and I think to myself 'I could have this done so much quicker if I could use PHP'.
Does anyone have any information on this subject? And FYI I do know PHP is meant to be a web programming language and is not meant to be run in a desktop application, but I'm intrigued :)