Tip: How to easily keep your Powerbook from trying to connect to internet when on the road and off line.
Go to Network panel in System Prefs, Under the 'Locations' popup, select 'Edit Location'. Duplicate any existing location, and rename it something like 'Off-line'. Now go to the 'Configure' popup and select 'Advanced'. On this screen uncheck ALL of the connection types - and Save. Now you can switch easily at any time from the new 'Apple' menu's location sub-menu. When you select your new 'Off-line' location, your Powerbook will not keep trying to connect to internet.
Mac OS X Hints
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