Lifehacker's Adam Pash has written a great primer on how to set up your computer so it will do different things depending on whether you are close with your Bluetooth phone, and on what wireless networks are available.
Using network and Bluetooth detection software, you can do things like mount networked drives, set default printers, enable/disable your screensaver, and launch applications based on what networks are available, what network you're connected to, and what Bluetooth devices are in range. Today I'll show you how.
These programs could be used, for example, to automatically start assistive software such as SmartNav or SwitchXS when you come close to the computer with your bluetooth phone, and to disable them when you leave so other family members can use the same computer.
The "wireless network detector" part is often good for detecting your location - home or school or work - and you can then change settings appropriately.
- Ricky Buchanan