MetaWeblog API
I've been working on implementing the MetaWeblog API for Something Emporium. You can see the automatically generated API documentation here - that's also the location to XML-RPC to for the API. This means you can use standard blogging tools (like ScribeFire) and your regular username and password, to post to SE. Like I just did!
I believe digg also supports this API. So, if you've got an account over there, you can can blog from digg.com. I don't know why you'd want to, but you can.
I believe digg also supports this API. So, if you've got an account over there, you can can blog from digg.com. I don't know why you'd want to, but you can.