One of the most important recent developments in consumer technology has been the dramatic improvement in Web-based applications. These are software programs that aren't installed on your own PC, but live on a company's server and are accessed using a Web browser. Such Web-based software has existed for years, but it was clumsy, slow and simplistic -- no match for locally installed software. Common techniques, such as dragging items around the screen, were impossible. Seeing the results of an action often required the Web page to reload. Now, developers are churning out Web-based applications that are so fast, rich and smooth they can hardly be distinguished from standard programs. And because they live online, these Web applications can be constantly updated; can run on both Windows and Mac computers; and can be easily integrated with other Web sites and services. One of the best examples of these slick new Web-based application is Picnik, a sophisticated, photo-editing applic...