Maybe... I routinely have over 50 on 3 computers.
I often find I get into a topic and don't have the time to finish it before I'm distracted or move onto the next. On my work PC for example it's easier to open new tabs up if I'm on the phone with a customer and I need to do something for them, we use so many internal systems also that having a few open on the CRM, the helpdesk ticketing, the core system, a few supplementary pages and on the support section isn't uncommon. I find it's easier to keep a window open on the search screen in the core app and remembering by position is easier than having to re-open it (though I do that too as I'm a bit muddled up which hence means more tabs :P)
At home I'm at uni so I might be browsing some things like slashdot and get sucked into a topic and end up on wikipedia 3 hours later looking at something entirely different that's caught my eye. Soon it's time to go out, clean the house, take a dump or floss my bear's teeth whatever and so I leave them open so I can return to it.
Of course, I tend to think "on the spot" so I'm the type of person who rather than have folders in their emails constantly relies on searching (i.e. i start from scratch as it's easier for my brain to think on the spot than refer to memory).
Each to their own .. let's just say the SSD made a huge difference to the time it took for my firefox windows to open .. (I will usually have another browser or two open too, and at work I run 2 actual computers on 3 monitors with a virtual on one .. won't mention remote sessions). Every person I've rented with or worked with always says I'm crazy 'cos of the windows - yet I know where everything is... :P .. What can I say I envy you people with memory :)