Brutal squirrel is a converter to hex digits (plain text) and back. Using it, you can use your favorite text editor (such as vi or emacs) as a hex editor. You can compose any binary file or text file with non-keyboard symbols directly as hex digits. It reads from standard input and outputs to standard output.
GTK+ Recent Files Scrubber is a compact, lightweight Python script which uses GTK's RecentManager to watch for updates to all globally-available "Recently Used" lists (the ones which appear in Open dialogs and the like) and filter out anything in the folders you blacklist. Blacklist entries are hashed to make reading the blacklist not worth the effort.