Alarm App that can be triggered from a remote server?

[Jace_TBL]

Does anyone know of an app that can trigger an alarm, which can be controlled from a custom remote server?

E.g. I have some script at my own webserver that (in case of some random event) can send a signal to this app, and then the app generates an alarm.
Obviously the app would have to identify with the webserver first, before the server can send anything specifically to my device or app instance.

I guess it's a bit like RSS, but one that triggers an alarm, rather than feeding news.