Gmail has a so-called "fullscreen mode" which ought to please me: it dedicates all of the browser's screen real estate to the message I'm reading. No pesky sidebars at all. Ain't it great? Well, it turns out I'm rather difficult to please.
What should I do once I'm done with the message? I will either want to delete it, to archive it, or to read my next message. But I can't do any of those in fullscreen mode! How come there's no button to come back to my inbox?
Okay, so this is a trivial problem with a trivial solution: just bookmark Gmail's inbox and be done with it! But of course, I wouldn't be telling you about this if I had settled for the trivial solution.
Here is my solution: widest gmail. It's a bookmarklet, so don't bother clicking on it now, it won't lead you anywhere. But if you put it in your toolbar, and click it once you're in Gmail's conversation mode, it will toggle the fullscreen mode on and off.