Suggestions for making "Addons" for a CI app?

[eluser]bobbytb[/eluser]
Hello,

How would one make their CI app extensible via addons or modules?

I have a basic web-app that and would like to be able to "extend" the application's features via addons/modules that I can create in the future. My app is a basic reporting app, and in my case these addons would mainly consist of new reports that may be designed in the future.

Im borrowing the idea of addons/modules from CMSes such as joomla/wordpress/drupal etc.

Ideally, I would like the end user would be able to install these addons/modules using their browser (as opposed to ftping the files across).
The newly installed addons would then be integrated into their existing system.

I am sure this should somehow be possible with CI and I know its not trivial, but at this stage I dont even know where/how to start.

Any pointers to concepts or suggestions would be helpful and are welcome!