MarcoPolo brings context-aware computing to your portable Mac computer. It allows your computer to determine its context through gathering evidence from your environment (evidence sources), using flexible rule-based fuzzy matching to make an educated guess (rules), and then performing arbitrary actions upon changing context (actions).
MarcoPolo's concept of contexts is a generalisation of a location, and encompasses more than just where your computer is. A context might represent what you are doing, or what else is going on around you.
MarcoPolo quietly stays in the status bar at the top of your screen (right-hand side of the menu bar), from where it can be configured to your own needs.
This review was originally posted on VersionTracker.com. I have been using MarcoPolo for about 4 or 5 months now and I absolutely love it. It makes handling moving from one network to another an absolute breeze and completely automatic. It automatically changes between my wifi networks and my 3G wlan card when I insert the card. It includes things like changing SMTP servers for different networks which network locations does not do. I highly recomend this utility for laptop users.