The Wikipedia List of revived languages is uncharacteristically brief and incomplete, and it includes moribund as well as dead languages.
A substantial number of Australian Aboriginal languages are involved in revival efforts.
Also, PRUSSIAN RECONSTRUCTIONS : Old Prussian. Which I found out about because their request for a Wikipedia was denied. The Wikipedia language committee are notorious spoilsports…
In the 1832 revision of Byzantine music, Chrysanthus of Prusa came up with a Greek equivalent of solfège, using the same derivation from acrostics of a hymn. So: Pa Vou Ga Di Ke Zo Ni.
To my surprise, there’s no decent online source on this (https://thmodocumentation.files…. p. 6 has the info in Greek).
EDIT: I say acrostic, but it was a rigged acrostic for the occasion. Chrysanthus’ actual intent was to put the first seven letters of the Greek alphabet into a set of CV syllables:
πΑ Βου Γα Δε κΕ Ζω νΗ