Building an API? - Interacting with a CI Application OffSite

[eluser]Corey Freeman[/eluser]
This may be a stupidly ambivalent question, but can someone guide me in implementing an API?

Similar to twitter followers/tweets, I'd like people to be able to pull their account info from my site (cloudreve.com/home/) and display it on their websites.

I setup an RSS feed but I'm thinking that's not the best way to do it?

[eluser]Georgi Budinov[/eluser]
If it is an option at all - an iframe widget is a cool thing - just like the ones from facebook.

Another thing you could do is a json feed just like the one from twitter - this way your users don't need server side scripting.

[eluser]danmontgomery[/eluser]
http://philsturgeon.co.uk/news/2009/06/R...odeIgniter

[eluser]Corey Freeman[/eluser]
Okay I've been reading up on Json, but could someone give me a quick example of using it with CodeIgniter?