What is the weirdest sound you have evolved in your phonology?

I'll start: fully phonemic [ə̃ː] <ȳ̃>

It started as a simple long /e/ in the proto-language, but it later evolved into a schwa in unstressed syllables and after uvulars (and later became phonemic as /e/ turned into /i/ in all environments). Then, a lot of vowels got nasalized as they merged with nasal codas.

Edit 1: Better wording and a spelling correction.