The browser is currently the number one tool you couldn't do without on any computer, but there's still room for change, and Opera shows us its vision for the future with the Opera Neon.
Making radical changes to a browser is ill advised (just like is is for any product used by hundreds of millions of individual every day) so, Opera opted to launch something completely different, needing not worry about its regular users complaining about wanting their usual Opera browser back.
The Opera Neon can be considered a prototype with a complete set of experimental features, some of which may find their way into the regular Opera browser (as well as other browsers) in the future.
In the design department Neon gets rid of tabs and opts for "bubbles", as well as a physics engine that hopes to provide a more natural feeling when interacting with its interfaces. We can also open two sites side-by-side within the same browser window; meaning you can use them both at once without having to click on each window first to active it. And capturing areas of a page can also be done instantly, allowing for easy share of those images with others.
Though it won't become your main browser today, don't be surprised if you notice some of its features influence the browser you currently use, over the coming months/years.