Rod McLaren tracked every browser tab he closed for more than a month. The total: 1725 tabs, an average of nearly 50 a day. I would be hesitant to undertake a similar tabulation for fear of learning the answer.
...is a weblog about the liberal arts 2.0 edited by Jason Kottke since March 1998 (archives). You can read about me and kottke.org here. If you've got questions, concerns, or interesting links, send them along.