Rudeness is always appropriate for private machines. So I name mine using euphemisms for female anatomy.

A female friend of mine didn't really appreciate the name "splitlips" and asked me to give the computer a "nice name" instead. So I added a CNAME for "nicename" and told her to use it. What she didn't realize until she actually logged into the shell was that I'd changed her Bash prompt to say "my nice name is still splitlips $"