Anyone know any usable scales in 21 or any of those other tuning systems? Or, even better, anyone know which intervals are haromonically consonant and which are melodically consonant?

Also, I started to get intereted in just-intonantion (again) after archeos post in chat thread. Anyway I could use just intonantion in fl?
I don't see any reason why you couldn't set FL to play notes some number of cents higher or lower. If it has such a function, you'd just need to find out the difference between notes in 12-TET and the notes in just intonation in whatever key you're playing.
Someones knowledge of guitar companies spelling determines what amps you can own. Really smart people can own things like Framus because they sound like they might be spelled with a "y" but they aren't.