When you start really using the internet, particularly websites, you quickly find yourself with multiple tabs in your web browser with sometimes cryptic names. It can be difficult to quickly discern which tab you want. Here is a sidebar add-ons for firefox (which you can install without administrator access). It puts the tabs on the side of your screen instead of on top, and it also includes thumbnails of the page, so you can see what the tab is before you go to it.
Also, if you want to quickly switch between tabs (even if you don't install the sidebar tabs), hit option-command-left/right arrow.
Hope this helps!