Open live writer is the first blogging software out for windows from where you can directly publish your post in your WordPress blog without logging into it. Its similar to MS Word where you can add pictures, video directly into your post from your computer. And the best part is its free and open source. So, if you write a lot of blogs and also want to do blogging offline and save your blog for later use, it would be a perfect fit fot you. Moreover, multiple blogs are supported also. With WordPress being the most popular cms for bloggers now a days, this would be a handy tool for bloggers. And it will not disappoint you.
If you want to download Open Live Writer you can download it from here.