I’m a Firefox fiend (extension count going up daily; Greasemonkey security fears acknowledged) and I just found out that if you have multiple tabs, you can go to tab N by hitting Ctrl-N. If you are like me and can’t visually scan horizontally for numbers (e.g. I have to count from left to right to figure out which tab I’m at – minor dyslexia-like thing) there’s an extension that’ll number the tabs for you.