Michigan State University's Center for Microbial Ecology hosts the Ribosomal Database Project (RDP), offering "ribosome related data services to the scientific community, including online data analysis, rRNA derived phylogenetic trees, and aligned and annotated rRNA sequences." Data, which may be used "for your own non-commercial research purposes," include Organism lists, Sequences (unaligned), Sequence alignments, and Phylogenetic trees; to download data, click on Download Area.