Blogarithm: You may have noticed the new format of the site (I like the blue better than the green), and also the box in the upper right. This is a link to Blogarithm, a project I've been working on with my friends Max and Fab. We noticed that we were often checking blogs only to find they had no new content. We created Blogarithm to fix that--you register your interest in a blog, and then receive email when it changes, a blogmail. We send at most one blogmail a day, containing a list of all your blogs that have changed in the last 24 hours. It is especially handy for blogs that update infrequently, but that you don't want to forget.
Among others, I use it to track Andrew Sullivan, who doesn't update on weekends, and Robert Cringely who only posts a column every few days. It doesn't work so well for Slashdot or Instapundit, because they update so frequently. But it is a handy way to keep track of the blogs I'm interested in.
Please try it if you are interested.