Emil Kozole has created a thought provoking font called seen that censors the 370 words on The Department of Homeland Security's list of words they track on the internet. Kozole's website has this to say about the project:
"Seen" is a font that has a preloaded set of sensitive “spook words” that the NSA and other agencies are using to scan through our documents. The typeface can be used in any popular software such as Illustrator, Indesign, Word or in a browser. It can be used normally to write text as any other font does, but once one of these trigger words is written the font automatically crosses it out. Therefore giving you an overview of your text in terms of these trigger words. This system highlights where you are potentially prone to being surveilled whilst also preventing you from potentially being tracked. Seen is an experiment of evasive and reflexive techniques around the topic of online privacy.
You can download the font here.