Description Language for Taxonomy (DELTA): a method for encoding taxonomic descriptions for computer processing that an be used to produce natural-language descriptions, conventional or interactive keys, cladistic or phenetic classifications, and information-retrieval systems.
Expert Center for Taxonomic Identification (ETI) Develops and produces scientific and educational computer-aided information systems. Also hosts the World Taxonomist Database (link: http://www.eti.uva.nl/tools/wtd.php) and the World Biodiversity Database
Integrated Taxonomic Information System (ITIS) Taxonomic information on plants, animals, fungi, and microbes of North America and the world.
Systematics page of the National Biological Information Infrastructure (NBII) - contains many pertinent links
ION - Index to Organism Names
NCBI - National Center for Biotechnology Information (a taxonomy browser for genetic information on malocostracan crustaceans)
Biology Browser - phylogenetically arranged links to many publications and internet resources on invertebrate taxonomy and systematics
Zootaxa - an online journal that publishes papers on animal taxonomy
National Science Foundation (NSF): Directorate for Biological
Sciences – Systematic and Population Biology
Southern California Association of Marine Invertebrate Taxonomists (SCAMIT) Homepage
National Benthic Inventory - National Benthic Specimen Collection
BIONet International (The global Network for Taxonomy)
Society of Systematic Biologists
Hennig Society
Systematics Association
Best of the Web/Systematics and Taxonomy

ARKive - Images of Life on Earth
An Essay on Biodiversity and Taxonomy by F. Boero
Census of Marine Life
Global Biodiversity Information Facility (GBIF) - provides rapid and free primary data about biodiversity to the global scientific community; includes a link to a powerpoint presentation outling the overall approach of GBIF
The National Biological Information Infrastructure (NBII) Homepage
National Center for Biotechnology Information (NCBI): Taxonomy Homepage
Tree of Life Web Project (TOL)
Species 2000
Centre for Marine Biodiversity (focus on northwest Atlantic)
OBIS - Ocean Biogeographic Information System - a database of global marine animal and plant distributions
Biodiversity Heritage Library - provides access to historical or obscure taxonomic literature

Invertebrates, vertebrates and plants from Florida
Gammaridean Amphipods of Florida - four volumes of keys to gammaridean amphipods of FL
Amphipod Newsletter
Geoff Read's Annelid Page
Annelid Resources**
Polychaetes of Chesapeake Bay and coastal Virginia
Ceph Base
Crustacea.net
Key to calanoid copepods at Crustacea.net
The Crustacean Society (TCS)
The Cumacean Page
FishBase
Octocoral Research Center - California Academy of Science's website for octocoral taxonomy
Tanaidacean Homepage
World List of Isopods
Echinoderms of the South Carolina Continental Shelf
Sea Slug Forum

http://www.seamonsters.noaa.gov/default.aspx - Benthic fauna of Gray's Reef National Marine Sanctuary (located in the South Atlantic Bight)

Classification of Recent Crustacea (from An Updated Classification of the Recent Crustacea, Martin & Davis, 2001)