Using BloGTK on Linux is easy to write and upload blog entries on WordPress.
Using Ubuntu (you may need to add multiverse and universe repositories), simply run:
apt-get install blogtk
Now open Applications > Internet > BloGTK.
In the Account and Prefernces window, use the following info:
Server URL: http://your.wordpress.com/xmlrpc.php
Bloggin System: MetaWeblog API
Now click SAVE and then OK.
In the main BloGTK window, select File Connect to get a list of your blogs.
Type away till your heart is content and then publish.
To make full use of the tags available on WordPress.com, such as
, open Edit > Custom Tags …
Tag Name: Code Tags
NOW CLICK +ADD.
When back in the main window you can simply insert the code tags by selecting your code tag and clickling the big green tick arrow.