FÜ etc
in utf8, there are 1408 (thus far) ways to write eff ewe see kay and get past filters
If you are going to try to catch all possible forms of all comon profanities
:: a gigabyte sized array, processing will take so long your site will shut down
as said before, does not really work, even with a good filter, policy and policing is required
This comes up often, in classes
students seem to enjoy finding homographs for swear words