I was searching for some information for a lecture on language development and stumbled upon this fascinating webpage. A few of the things I learned:
The language with the fewest sounds (phonemes): Rotokas (11 phonemes)
The language with the most sounds (phonemes): !Xóõ (112 phonemes). Approx. 4200 speak !Xóõ, the vast majority of whom live in the African country of Botswana.
Here is a video about saving Rotokas:
You can hear !Xóõ spoken here:
The website does make one mistake it claims:
Language with the fewest words: Taki Taki (also called Sranan), 340 words. Taki Taki is an English-based Creole spoken by 120,000 in the South American country of Suriname.
Actually, Toki Pona has only 120 words.