> what is the reasoning for the airport base with or without a modem? > if one's computer has a modem, it doesn't need a base with a modem? If you currently have to use a dialup connection but expect to get cable or dsl in the future, this would be a good thing. If you have broadband now and want to be able to switch to dialup on a network in case of broadband failure, this would also be a good thing. If you have broadband and want to use the modem as a fax, you would need this combo.