Technorati is the largest blog directory in the world. If you have started a blog, you will want to claim it at Technorati after you have written about ten good posts. Just sign up for a free account and follow the instructions for claiming your blog. It is best to do this before your blog has a large readership so that you can make the most of this service.
Technorati is an excellent source to drive targeted traffic to your blog. This is accomplished with Technorati tags, which are the keywords you use when writing your blog posts. When you tag one of your posts with a specific keyword or keyword phrase, anyone searching on Technorati for that phrase will find your post.
I also recommend taking a look at the top 100 blogs (according to Technorati) to see if there are some you are interested in subscribing to. You will be amazed at how much you can learn simply by reading some of these blogs, written by some of the most knowledgeable people on the internet. Technorati also has it own blog, where you will be able to find out what is going on with technorati at any given time.
Blogging will become more productive for you if you utilize the services available at Technorati.