I don't ask for recommendation! (just wanted to say that; anyway it doesn't matter now as the question is closed)

I've seen some advertisements about home alarms that notifies me that something is happening in my house. None of them mentioned programmability (with real programming language like e.g C, assembler, whatever). As a programmer I'd like to have a possibility to add some behaviour, that is not part of the alarm itself. This might be:

• take snapshots of all cameras in a house and send it to some email
• send email, twitter message, skype message to some predefined account
• send email to a police (silly, I know)
• start turning the lights on and off (scary, right?)
• etc. (would be veeery challenging with assembler, I know; but lets suppose I can use some more high level language)

I don't expect that there is a alarm system capable of this stuff, that's why I'm looking for a programmable module.

Question: Is it even possible? Is it good idea (my program could crash and cause instability of the system).