South Africa's Working for Water program is close to launching production of their new "eco-friendly" coffins, made using the wood of invasive plants, according to this story from IOL. The idea behind this is that the invasive trees and shrubs need to be cleared anyway, and building coffins from the wood will provide employment for former prison inmates. The project was awarded funding following a contest held by the World Bank Development Marketplace that received more than 2500 proposals.
I can't seem to find a list of what species are being used to make the coffins, but I assume certain species must provide more suitable wood than others. And in case you still had a happy thought in your head, keep in mind that there is a reason South Africa has such a demand for cheap coffins - the country is being overwhelmed by HIV and AIDS-related deaths.
Update:Download your own morbid coffin poster here (.pdf).