The Samuel P. Harn Museum of Art at the University of Florida has an excellent exhibit called Between the Beads: Reading African Beadwork. Their explanation of the history and meaning of African beadwork is here. (As always, click on the photos if you want to see a larger version.)
Male Royal Ancestor Mask (Mbwoom)
Beaded Crown (adenla)
Zulu beadwork traditions are fascinating because the colors, shapes, and patterns convey messages about courtship and marriage. You can read about the language of Zulu beadwork here.
The work below by a woman named Bongiswa is part of a great rural training and employment project called Ubuhle.