Great tip that came from the socialcmsbuzz site. If you are running a Wordpress blog like this one then you've probably noticed the revision control and tracking features. Each time you make a change a new version is created and Wordpress keeps track of what changed between versions. If you accidentally delete a post, get hit by a virus or are just terminally cranky, you can go back to find and redo/undo your revisions and changes.
However, the Wordpress implementation (2.9.1) appears to keep unlimited (or at least just limited by available space) revisions and these can take up a lot of space. Fortunately there are plugins to help. I am using the Wordpress Revision Control Plugin which helps you setup how many revisions you want to keep by post and or page - going forward. I am also using the Delete Revisions plugin which enables you to go in and clean up (i.e delete) past revisions that have already been stored - even on my relatively small blog, there were hundreds (of course I do revise a lot).