But I think if you get a Gmail account with non identifiable information. Then access Gmail through Tor (There's a Tor plugin for Firefox) you've done enough to make it extremely hard to track you down.
Or my favourite: a virtual machine with a snapshot of it's state just after the install of all your necessary programs, HDD set to read only (like you can do in parallels) and used from there...
Anonymous Blogging with Wordpress & Tor
http://advocacy.globalvoicesonline.org/projects/guide/
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Handbook for Bloggers and Cyber-Dissidents
http://www.rsf.org/IMG/pdf/handbook_bloggers_cyberdissidents...