With Yahoo’s Zimbra Desktop Beta all users of Yahoo Mail, @ymail and @rocketmail users — can access their mail and calendars offline.
Yahoo! Zimbra Desktop is the next-generation email application that makes email easy again. Zimbra Desktop is free for anyone use and is currently a ‘Beta’ version.
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Live Mesh is Microsoft’s combination of client software, services, and developer tools.
Live Mesh will let users and developers automatically or manually synchronize data among devices and to the Web, share content, remotely access Internet-connected devices, create Web apps that are accessible offline, and client apps that connect to Web services.
Live Mesh Features