Start program in response to system events (like ip address changes, etc.)?

Question

I want to start a program in response to system events, such as:

• IP address changes
• WIFI connectivity changes (whether I'm connected, and/or which network I'm connected to)
• Volume (as in disk) changes
• User logs on or off
• System shuts down or restarts

Is there anything built in to do this, or is there a 3rd party tool that can do this for me?

Answer 1

ControlPlane has many of the functions you're looking for, though I don't think it has any rules for connected users. I've been using it for a few months on my work MBP to switch between home and office and it's been quite good.