I had not heard of "D'ni" before and took a look at that one. I was enchanted to see that its alphabet is comprised of constanents and vowels.Here you can find a collection of links to conlangs, artificial languages, auxiliary languages, etc.
F
I'll borrow a line from the Brazilian_dude here and say I don't know squat about this. But I'm guessing: the constanents are "stationary" sounds (and the vowels are...not?)...
-gailr