Why not have a web browser feature that can do on-the-fly search and replace of keywords in the content? The user could supply a custom list of words or phrases and their replacements. This would be pretty easy to do, and could have a wide variety of uses.
Doublespeak Replacement: Set it to automatically replace the phrase "security contractors" with "mercenaries," and so on. The news might seem realistic again.
Spin Generator: This type of list would add "flavor" by replacing neutral terms with more charged ones.
Foul language eliminator: Make the Web PG-13! Replace "hell" with "heck," or replace c********* with "scoundrel."
Medievalizer: Replace "the" with "ye," "you" with "thou," etc.
Compressor: Replace wordy phrases with shorter ones. Replace "at this point in time" with "now," etc.
Super compressor: Replace "You know what I'm saying?" and "At the end of the day," with ""
How about it? Will we see this in some future version of Mozilla?