Track and manage your time online with 8aweek
When you install 8aweek and then reboot Firefox you should see a new browse toolbar. Click on the View habits and you'll be taken to a web page showing how much time you've spent on every web site while logging was enabled. 8aweek seems to know the difference between a page you're actively looking at and a page that's open in a background tab and will only log pages in the foreground. But it doesn't differentiate sub-sites. For example, Gmail and Google Reader are lumped together as Google. And since Download Squad's blogging client Blogsmith is hosted by our parent company, AOL, 8aweek reports that we've been spending a lot of time at AOL.com.
You can also click on the restricted tab to add pages that you don't want to spend too much time on. Then click the preferences tab to determine how much time is too much. By default, this setting is 30 minutes. There doesn't appear to be a way to set different time limits for different sites.
The browser toolbar also lets you "save" links to pages you want to come back to later. So you can use 8aweek as an alternative to Read it Later or Instapaper, but with a nagging/analytic feature.