Want to open a new tab? Hold right-click and move up a millimeter.
Want to go back or forward? Hold right-click and move left or right a centimeter.
Want to Stop a page from loading?Down.
Want to close a tab?Down, right. (an L shape if you will)
Want to reload a page?Up, down.
Want to open your closed tabs?Down, left, up, right.
Want to switch between two tabs?Up, left for a tab to the left; Up, right for a tab to the right.
[sub](Or, mouse-wheel down and scroll to the one you want if it's more than one away)[/sub]
Want to open up the page history of this specific tab? Mousewheel up, scroll to the page you want to get to. Basically the extended version of back/forward.
A lot of things you can do and you can custom set your own directions (even to 8 cardinal directions instead of 4, but I get a lot of accidental combination inputs so I don't bother), it's basically set up to make you not need to spend any time navigating (or save you immensely in time), and makes it so you rarely have to put your hand on the keyboard, as the mouse does a lot of the functionality via firegestures.