The West African Arabic Manuscript Project catalogs over 23,000 Arabic manuscripts in collections across West Africa. Currently they have a bilingual searchable database and the ability to browse by topic headings. According to their home page, they are working on linking records to scans of the manuscripts themselves.
While I’m looking forward to having access to digital scans of the manuscripts, this database is certainly renewing my interest in a trip to West Africa. Too bad travel to the libraries in Timbuktu is not as easy as it was.