A constructed language supposedly culture neutral, but drawing vocabulary, phonemes and general sound and feel heavily from western indo-european languages, particularly italian, of which its polyglot creator was especially enamoured. Spoken by about two million esperantists worldwide, largely at conferences, except for a strange minority of esperantists who met and fell in love at a conference and use it as their main language together, which also accounts for the only people who speak it as their mother tongue - their kids, though you can bet they've learned another language or two so they can actually communicate with oh, the kids at school and everyone else. Sci-fi guy Harry Harrison (y'know, the Stainless Steel Rat series) was an Esperanto freak, featuring it prominently in many of his books. Lots of internet sites offer free correspondence lessons in Esperanto.

My favourite phrase: "Via panjo!" (yo' momma!)