Tab Candy is currently in Beta testing at Firefox and I'm really excited about it. I'm one who has a dozen or so tabs open at once, currently I have 17 open . Anyways with tab candy you can organize them, set them into groups or do a quick look to see what you have by looking at a little snap shot of them. Here is a little video that explains it much better then I can...
Now if your ultra excited you can test this out and get the new version of Firefox that is currently in Beta testing CLICKY Just remember your getting it bugs and all.
If you want to read more check out Aka Raskin's blog.
thats neat. I think i'll wait till the real version comes out tho t i dont need no bugs.
Olympus
Single & Not Looking
Looks sweet. If ya want the core functionality right now you can use the two addons I've been using for a pretty long time now. TabGroups Manager will organize your tabs into renamable groups, and you can hibernate groups to conserve some memory if you want to, and TabScope to show a small popup image over each tab so you can see at a glance what it is.