It seems that every day we discover how complete Safari's support of tabs really is. Looking for another way to open tabs? If you have a three-button mouse or two-button with scroll wheel button (like mine, a Logitech WheelMouse), the scroll wheel works but the button has typically been useless. Not anymore. Click the scroll wheel button over a link and the link opens in a new tab. Excellent.
[robg adds: To make this work with my Microsoft Intellipoint mouse, I had to disable Intellipoint in Safari, in which case I lost all mouse features but the middle button works as described. A better option was to add a custom setup for Safari, and just set the middle button to send a Command-click event. My middle button is set to "Autoscroll" as a global preference; I don't recall if that's the global default or not.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20030418134605451