If you have any laptop Mac with Bluetooth connectivity, this info from Wired exposes a risk. See this article with settings for info. If you do not use any Bluetooth devices (wireless keyboards or mice, or direct links to iPhone or PDAs) be sure to turn it off in the Bluetooth menu or preference pane in System Preferences. It saves your battery drain. (So does turning off AirPort if you are on battery but not connected to a WiFi spot.)
To change the setting in your default Bluetooth settings, you must first turn it ON, then click the Advanced button, then in the drop-down menu uncheck the box "Allow Bluetooth devices to wake this computer."
From today's TidBITS:
**Bluetooth Default Setting Poses Risk to MacBooks** -- Wired.com's
Brian X. Chen reports on a potentially dangerous default Bluetooth
setting found on Apple notebooks. The setting enables a Bluetooth
device to wake a machine even if its lid is closed. For a user
packing a MacBook and Bluetooth mouse into the same satchel, this
default could result in an overheated disaster. (Posted 2009-05-08)
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