For me, web applications are all about performance. With modern web servers and broadband, web applications can, and should, feel fast and responsive. The goal should be to make it feel as fast as a desktop application. This mini-application has html pages that are each under 6kB! That means page load times should be measured in milliseconds, not seconds. Fast performing web sites are a joy to use, and make for happier users.
Web applications need to respond quickly not just to user actions, but to changing business requirements. This application uses simple, elegant design patterns such as Model-View-Controller (ASP.NET MVC) to separate the various concerns of the application. This makes it easier to make changes than with many older web application frameworks, such as nearly all PHP and ASP Classic based sites, and most ASP.NET Web Forms sites too.
This application was also built to demonstrate some of the capabilities of ASP.NET MVC, JQuery UI and CSS - a knockout combination.