Before leaving, I enter my passport info online and printed my boarding pass at home.

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Lots of services offered by its online-access business, MSN, use Passport, such as MoneyCentral and a digital photo site.

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Other services that can't be reached include Windowsupdate.com, which contains updates for the Windows operating system, Passport.com, Microsoft's online identification service, and bCentral.com, a portal for small and medium sized businesses.

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