Tools to replace swear words with grawlixes: symbols suggesting anger and obscenity
A headline earlier today benefited from some creative obfuscation of the word "motherfucker", and there's no better method than grawlixes: a set of now-traditional characters used to suggest anger, confusion, obscenity, resentment and other likely emotions behind the language. Merriam Webster:
What the #@*% Is a 'Grawlix'? Sometimes the symbols used for a grawlix might be selected specifically for the word it's meant to represent. In the title $#*! My Dad Says, for example, the resemblance of the dollar sign and octothorpe to the first two letters of the word (you know the one) is probably not coincidental. The grawlix: it's some good $#*!.
Tinwatchman created an open-source library that "makes the web swear like a cartoon" if you want full service, but software developer Sampo Juustila simply collected the best unicode characters and emojis in a nice, easily copied-from page. Advanced grawlixen might want to roll their own from the unicode miscellaneous symbols block.
There's now an emoji called serious face with symbols on mouth - 
- that fits a three-character grawlix into a single characer, but it's so tiny you can barely see the grawlix at standard type sizes.
Blambot offers Potty Mouth, a free-of-charge font of perfectly-drawn grawlixes for use by artists and designers. (Its exemplar is the image on this post!)
The grawlix originates in American comics, and was defined by Mort Walker in a 1964 article that was later collected in the 1980 book The Lexicon of Comicana [Amazon].
Wikipedia collects a few other examples:
Agitrons: wiggly lines around a shaking object or character
Blurgits, swalloops: curved lines preceding or trailing after a character's moving limbs
Briffits: clouds of dust that hang in the wake of a swiftly departing character or object ()
Dites: diagonal, straight lines drawn across flat, clear and reflective surfaces, such as windows and mirrors
Emanata: lines drawn around the head to indicate shock or surprise
Grawlixes: typographical symbols standing in for profanities (
Hites: horizontal straight lines trailing after something moving with great speed (); or, drawn on something indicating reflectivity (puddle, glass, mirror)
Indotherm: wavy, rising lines used to represent steam or heat (,
)
Lucaflect: a shiny spot on a surface of something, depicted as a four-paned window shape
Plewds: flying sweat droplets that appear around a character's head when working hard, stressed, etc. (,
,
,
,
,
,
)
Quimps: planets resembling Saturn, used to replace obscenities
Solrads: radiating lines drawn from something luminous like a lightbulb or the sun (, a1/4, -,
,
,
, a, -, -, -, )
Squeans: little starbursts or circles that signify intoxication, dizziness, or sickness ()
Vites: vertical straight lines indicating reflectivity (compare dites, hites)