Firefox has built-in keyboard shortcuts for quickly navigating directly to the tab you want to get to. This is very useful when you are using Google Reader or Bloglines to read RSS feeds, and you’ve opened up a bunch of tabs. Before discovering this trick, I always used Ctrl+Tab to navigate back, or had to use the mouse.
Ctrl + 1 will always select the leftmost tab.
Ctrl + 2-8 will select each of the tabs in order from left to right.
Ctrl + 9 will always select the rightmost tab.
To see this “in action”, notice that I currently have the middle tab selected:
I hit the keyboard shortcut Ctrl + 1, and I’m instantly taken to the first tab again:
This can save you a ton of time if you like to open a bunch of tabs.