This looks like a very interesting project. Randy Rants’s SharpMT is a Windows offline editor for MovableType. It is using XML-RPC to post to MovableType, and is quite handy if you aren’t always online, but still want the ability to work on blog postings.
The project is in a very active phase right now, with new builds being released almost every day. Its still in Beta, so if you start using it – you might find yourself updating quite often. It requires the Microsoft .NET Framework.
Things to (possibly) come include a spell checker and a “WYSIWYG” editor.
[Via Anders Jacobsen’s Blog]