iPhoneDrive is a new Mac OS X application that lets you use your iPhone for file storage, much like an iPod in disk mode. The tool allows you to drag and drop files from the Finder, but needs to be installed on any Mac to which you want the iPhone to accept or send files.
iPhone Drive shows how much space is available on the iPhone and has options for copying to the iPhone or from the iPhone as well as creating folders -- simple but effective.
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