Scroll-wheel-click in Safari
Here’s another I thing discovered in Safari. (Again, maybe it’s old news, but maybe not.)
If you have a mouse with a scroll wheel, then if you scroll-wheel-click on a link (or bookmark in the Bookmarks Bar), then the link will open in a new tab.
This is quicker than ctrl-clicking (or right-clicking) and choosing Open Link in New Tab.
(It probably requires that you have tabbed browsing turned on, of course.)