Most of the computer-related tips I know are things I discovered by mistake due to hitting the “wrong” key or something like that. This one is no exception.
You may already know that holding down the shift button while you left-click (with your mouse) on a hyperlink, the destination page will open in a new browser window. Now that browsers have tabs (remember when they didn’t?) wouldn’t it be great to use them instead of cluttering up your system with lots of open windows? In a similar fashion, you can hold the Ctrl key down while clicking on a hyperlink and it will open the destination page in a new tab, instead of in a new window.
But today I learned a way that is even quicker/better — instead of clicking the hyperlink with the left mouse button, click it with the scroll wheel. Yes, really, if you push down on the scroll wheel while your mouse pointer is over a hyperlink it will open the page in a new tab and (this is the best part, in my opinion) the focus will remain on the page you are currently viewing. This works in Internet Explorer and Firefox for sure, and may very well work in other browsers too.
This functionality is great, for example, if you are in Google Reader and you want to open all the interesting stories at one time without hopping back and forth between the Google Reader tab and the story tabs. Hopefully this tip is handy for you!
Edit to add: it may be necessary to make changes to your mouse settings for this to work. For example, the Logitech wireless keyboard/mouse that I run on my desktop computer defaults to a different function if I click the scroll-wheel. I was able to easily make the switch in the Logitech software. On my laptop, I was able to define a zone in the bottom right of the touchpad that works as a middle click if I tap there.