Uses of the TLA XXX:

1. For the Roman numeral XXX, see 30 (number)
2. As a reference to Amsterdam, after the city flag (this may be linked to the use of XXX in Pornography).
   

   

   Flag of the city of Amsterdam.
3. The ISO 4217 currency code for no currency
4. The standard Morse code prefix for urgent communications (q.v. SOS)
5. xXx (movie), a 2002 action film starring Vin Diesel
6. ArXiv.org e-print archive, formerly known as xxx.lanl.gov
7. A reference to the Straight Edge lifestyle common on Tattoos
8. As a reference to Pornography e.g. X-rated movies - XXX movies
9. Former TNA Wrestling stable consisting of "The Fallen Angel" Christopher Daniels and "Primetime" Elix Skipper and Low Ki
10. SMS (or text message)speak for "kiss kiss kiss", a goodbye salutation commonly used.
11. Mackeson XXX Stout is a beer.

See also X, XX, XXXX.