MarcoPolo – Context-aware computing for Mac

MarcoPolo is a very cool (free) application for MacOS X that uses information about the current state of your computer, or evidence, to automatically perform actions.

For example, one can use MarcoPolo to automatically change the Network Location if an ethernet cable is plugged in or a specific Wi-Fi network is present (useful if you need a different network location at home and at the office), automatically open up an application if a USB device is plugged in, or shut down certain applications and mute the computer if a projector is plugged in (useful if you want to avoid that embarrassing IM message in the middle of a talk).

MarcoPolo can use many different sources of evidence:

• Attached Audio Output devices (headphones/internal speakers)
• Discoverable Bluetooth devices
• Advertised Bonjour (Zeroconf) services
• Attached FireWire devices
• Assigned IP addresses
• Ambient Light level
• Attached Monitors
• Active Network Links
• Power source (power adapter/battery)
• Running Applications
• Current Time Of Day
• Attached USB devices
• Visible WiFi networks

and can perform the following actions:

• Set your default printer
• Change your desktop background
• Enable or disable particular firewall rules
• Set iChat status message
• Set the default IMAP or SMTP server for Mail.app
• Mount network shares (smb://, afp://, etc.)
• Mute or Unmute system audio
• Change OS X network location
• Open a file (an application, a document, etc.)
• Quit an application
• Enable or disable screen saver password
• Start/stop screen saver
• Change screen saver idle timeout
• Run a shell script
• Turn on or off Bluetooth
• Turn on or off WiFi (AirPort)
• Establish or disconnect VPN

that can be grouped into contexts, such as Work or Home.

But the key strength of MarcoPolo, which makes all this a lot of fun, is that you can assign different probabilities to different sources of evidence. So for example, you can use a specific level of lighting as a 60% chance that you are at home, and the fact that an ethernet cable is plugged in as an 80% chance that you are at work. All the weighted sources of evidence are added up, and the final context is automatically chosen!

Have you used MarcoPolo before? If so, what cool uses have you found for it? And if you are a Linux or Windows user, have you found an equivalent application?