It looks like soon you'll be able to integrate Texecom directly with Z-Wave and a bunch of other stuff:
http://www.texe.com/uk/technology/connect/
A more expensive option is Control4 (although if you buy a second hand HC250 controller off ebay and find a cheap integrator it's not ridiculous), but I know that integrates pretty well via IP. You can then also do lots of extra programming logic (like have your lights flash when the alarm comes on, send you an email when a PIR is triggered when armed, send you a snapshot from a camera when a door contact is opened etc, pretty much anything you want).
http://www.texe.com/uk/technology/connect/
A more expensive option is Control4 (although if you buy a second hand HC250 controller off ebay and find a cheap integrator it's not ridiculous), but I know that integrates pretty well via IP. You can then also do lots of extra programming logic (like have your lights flash when the alarm comes on, send you an email when a PIR is triggered when armed, send you a snapshot from a camera when a door contact is opened etc, pretty much anything you want).