There is the suggestion made in the article that you can get any random IDN, and to the best of my knowledge that is not true. There's something about collating

There is the suggestion made in the article that you can get any random IDN, and to the best of my knowledge that is not true. There's something about collating characters (there is no collation order for poop, hearts or astrological signs) only, and it has to be in only one character set (no mixed languages). That said, you are free to create "<poop>.example.com", presuming you own example.com. Indeed, "`rm -rf *`.example.com" is a valid FQDN according to the DNS (protocol) as opposed to The DNS (implementation).