The Bassa Vah script was developed in the 19th century for the Bassa language in Liberia. It fell out of use but was revived in the early 20th century by Dr. Flo Darvin Lewis, who had discovered that descendants of slaves in Brazil were still using the script. It was used in printing and education, and is still used to some degree [need more info].
Sites with information include:
It is not yet encoded in Unicode, though it figures in the Script Encoding Initiative's database - see http://www.linguistics.berkeley.edu/sei/USR.html#n011 . Michael Everson has a draft chart at: http://www.evertype.com/standards/iso10646/pdf/bassa.pdf