Colloquy for iPhone -- Push Notification Server
Colloquy is a great IRC client for Mac, as well as the iPhone. Currently, to run Colloquy on the iPhone you must purchase the mobile version from the App Store. The other option is to download the source and build it yourself, but you must be a registered iPhone developer to run it on an actual iPhone. Also, if you intend to use push notifications (via the Colloquy ZNC plugin), you must have a push certificate as well....