There are many ways to open a new window or instance of an application. Simply selecting it again from the programs list; right-clicking its icon on the taskbar and using the context menu; or typing its name into the Start Menu search box... the list goes on. But they're all less convenient and slower than using Shift or the middle mouse button.
Yes, that's right. As Reddit user "whyUsayDat" notes, you can just hold down the Shift key and click on the application in the taskbar to start a new instance. Alternatively, you don't even need to use the keyboard as another user, "NonFrizzante", notes:
Middle mouse button click does the same thing.
Other useful middle mouse button clicks:
- Closing browser tabs
- Opening a link in a new tab
- Opening all links in a bookmark folder at once, each page in its own tab.
- Quick scrolling
This is one of those shortcuts that, if you didn't know about it previously, will make you apply your palm to your forehead. I certainly had no idea it existed.