That wheel in the middle of your mouse is good for more than just scrolling—in fact, the button can do quite a bit. Here are some of the oft-ignored shortcuts built in to the middle mouse button.
If you're on a laptop and don't have a middle mouse button, you can probably still perform many of these actions. Many laptops will simulate a middle click if you press the left and right buttons simultaneously, or you can add that ability with a program like AutoHotkey. Of course, most of these things are easily accessible from other places, too—they're just a bit quicker if you have a middle mouse button.
You'll also notice a lack of Mac shortcuts below—likely because Mac mice don't usually have a middle mouse button. You can add in a gesture with an app like MiddleClick for the browser shortcuts, if you so choose.
In Your Browser
Your browser—whether it's Firefox, Chrome, or even Internet Explorer—makes better use of the middle mouse button than anything else. With it, you can:
Close a tab by middle-clicking on the tab
Open a link in a new tab by middle-clicking on the link (this also works in the address bar's drop-down menu and back and forward buttons)
Open all bookmarks in a folder at once by middle-clicking on the folder in your bookmarks bar
Enable auto-scroll by middle-clicking on a web page
Paste text in Firefox with a middle click, by enabling the
middlemouse.pasteoption in about:config
You may be able to add more functionality to your browser with extensions, but these are the middle-click shortcuts built into most browsers.
In Windows
Apart from the browser shortcuts, Windows has a few other shortcuts built-in for the middle mouse button. You can:
Open a new instance or window of a program by middle-clicking its taskbar icon
Close a window by hovering over its taskbar icon, then middle-clicking the thumbnail that pops up
Enable auto-scroll in Microsoft Office by middle-clicking in the document
Of course, you can always use an app like AutoHotkey to map the middle mouse button to just about any action you want. You may also have some limited customizability in your mouse's settings, and some third-party apps may come with middle mouse button functionality built-in.
In Linux
We'd be remiss not to mention Linux, which has one particularly famous (and awesome) middle click shortcut: if you middle click in a textbox, you can paste text from the clipboard in just about any app. It's pretty darn handy!
The middle mouse button doesn't get nearly as much attention as its right and left brethren, but it's still a useful tool if you can remember what it does. Hopefully this gives that button a bit more play in your productivity routine. If we missed any good middle-click shortcuts, let us know and we'll add them to the list!
Title image remixed from Molodec (Shutterstock) and Tribalium (Shutterstock).