A conlang from the early 1800's in which the syllables were do re mi fa so la and ti. Music could be spoken and text could be rendered as music.
mi'e jezrax
I skimmed the docs at the first link, and found it interesting. I was most impressed with the non-verbal abilities of the language. Does lojban have any non-spoken aspects? Or, differently, is there any LojbanSignLanguage? --Skorgu