MarsEdit - MarsEdit is a desktop blog editing application for the Mac. It provides an offline interface to most popular blogging systems. WordPress, Blogger, Tumblr, Movable Type, and many other systems are supported.
WriteNext - The writing application that boosts your writing. Increase focus and writing performance and reduce distractions by separating your creative writing from other activities. Let writing be the only activity you perform in the writing application.
BlogDesk - Blogging should be simple, but it gets complicated and time-consuming if you are serious about it.
Stashany - Online notepad for developers
Open Live Writer - Open Live Writer makes it easy to write, preview, and post to your blog.
Writebox - Writebox is a simple and distraction-free text editor for Chrome and iPhone/iPad.