- Download and install QTTabBar here.
- You should now see a new toolbar in Windows Explorer. Right-click an empty space on the bar to bring up QTTabBar's extensive Options menu. There's a lot of customization possible, but for most users, the defaults are fine.
- There are two ways to open a new tab. The simplest is to hit Ctrl-N; this clones the current tab, but you can easily browse to whichever new folder you like. The second is to click the scroll wheel on your mouse when highlighting a folder; this opens that folder in a new tab.
- Things get more familiar from here. Ctrl-Tab lets you navigate between tabs, and you can see folder contents easily by clicking a tab's icon.
There's quite a bit more you can do with QTTabBar, including dragging and dropping, improving readability, and more. It extends the functionality of Windows Explorer quite dramatically, I think, though I occasionally see somewhat slower response time. It's a trade-off I'm willing to make.
Thanks to MakeUseOf for the link!