When the Chromebook first came out, I didn't find the "live in a browser" idea very compelling. But I spent a little while today looking at a couple of things that may change my mind: extensions that operate as light, attractive, highly focused apps. After a while, I can see that it could be quite possible to live within Chrome's tabs, especially as the apps and data are portable across Windows, the Mac and Linux (but not, alas, the iPad, although I imagine this will change eventually). First up: Do It (Tomorrow) . Its user interface will make you laugh. Click to open the book and you get two pages: Today and Tomorrow. No categories, no priorities, no subtasks, no Getting-It-Donnybrooks. You can choose between two typefaces. After you type in something to do, you have three options. 1. Click on it to draw a line through it. 2. Click on a little arrow to move it to Tomorrow. 3. Don't do anything. It stays on Today. That's it! I realize that such a ex...