Just downloaded and installed and posting this via Open Live Writer . Remember the lovely (but dead) Windows Live Writer from Microsoft? Well this is a forked version of that which is open source, based on MIT license.
The editor is offline and is very similar to word and can support a number of blogging platforms – including the common ones as you would expect. You can muck around the code (zip) or check it out on GIT . It is still work in progress of course (e.g. Plugin’s are not implemented yet). Irrespective, hugely grateful to Scott (Hanselman) to get this going.