Do you know that the middle mouse click is not as useless as it seems to be? There are several useful things that it can do in a browser.
1. Clicking the middle mouse button (by pressing down the scroll wheel) on a link in a browser will open the link in a new tab.
2. Clicking the middle mouse button on an open tab will close the tab.
3. Clicking the middle mouse button on a website will turn the cursor into a autoscroll button. You just have to move your mouse to scroll up/down/left/right the webpage. (Left) Click anywhere to deactivate the feature.