I also use a small amount of tabs, usually under ten. When I want to go to something, I want to immediately be able to click it without having to spend time searching for it. Sometimes I watch over coworkers' shoulders as they are navigating their browsers, and they definitely spend a significant amount of time looking through tabs trying to find what they need. There is a terrible, visible lag time between asking them to navigate to a certain page and them actually being able to find and go to the correct tab. Maybe my coworkers are just inefficient at managing large amounts of tabs, but I have yet to see someone who is.

Having fewer tabs might also keep one more focused because there is only so much in front of you at a time. You don't have to process through a bunch of data that is unrelated to the current task at hand.

I feel the same way - it bothers me to have tabs open that I'm not actively working on (or, I feel like I need to actively remember the context of all my tabs). When I get to 12 or so I close any tab that I don't feel like I'll want to return to in the next hour.

Getting nervous because your computer starts slowing down or swapping because of the number of tabs open, or because you can't read the tab titles or see the favicons anymore? Firefox doesn't have those problems. ;)

I also get tab-induced anxiety. I have to close them and organize them when it gets ~10 or I can't keep browsing.

On the other hand, my desktop is an unorganized mess of random files...

Same here, if I start needing to scroll through open tabs it means I should immediately start closing some.