Index Fungorum, an international project to index all formal names (scientific names) in the Kingdom Fungi. Somewhat comparable to IPNI, but with more contributing institutions.
Another difference is that where IPNI does not indicate correct names, the Index Fungorum does indicate the status of a name. In the returns from the search page a currently correct name is indicated in green, while others are in blue (a few, aberrant usages of names are indicated in red). All names are linked to pages giving the correct name, with lists of synonyms.
Index Fungorum provides LSIDs for records in its database.
Index Fungorum provides a SOAP web service for searching its database and retrieving records. The WSDL file describing the services is here: Fungus Web Service