Today's blog of the day is not really a blog, but a screencast. Dedicated to Ruby on Rails, the Railscast offers (as of today) 46 episodes of short, targeted practical advice on various aspects of Rails development.
Unlike some other screencasts who try to record the screen action as MPEG movie, this one is perfectly legible. In addition to the Rails enlightenment, you can also enjoy the speed and aesthetics of using TextMate - with many great Ruby editing shortcuts and beautiful OS-X typography.
Available as subscription in iTunes - search for Railscast.