I've set iWork '09 (I only use Keynote and Pages) to create automatic backups of the files I'm working on. This works fine, but sometimes I get these temporary backup files that I can't delete. I usually work on files on my desktop, and I just don't want the clutter while working. Upon trying to delete, I'm told this file can't be deleted (even if no iWork apps are running any longer). The file remains there until I logout or reboot. It's an additional (second) backup file and I don't know what purpose it serves. Unlike other backups, this one doesn't have a preview of the document in the icon (instead, it's just a regular pages/keynote file icon) Eventually it accumulates and begins to look ridiculous, see the screenshot of the right side of my desktop below. That's all the same file. The ones with no preview can't be deleted.