Jonathan Schwartz, Sun's CEO, has a blog post about office productivity and the vision for sharing information over the Internet as your 'workspace'.
Using Internet storage is something that many different companies have tried over the years, and the level of success and usability depends on a number of different parameters.
First up, the services themselves are varied, but are often based around a single idea that can be extended or expanded into other areas. For example, Apple's .Mac service is based around the iDisk concept, which is then married up with additional functionality like email, Photosharing, web sharing and synchronization and backup services designed to improve the integration and functionality of Mac OS X. For example, I share my address book, mail account info, keychain (stored passwords), and bookmarts between my desktop and laptop.