ORTHOFIND is a method for identifying functionally equivalent orthologues (homo-orthologues) using sequence information and SwissProt annotations. The draft copy of a paper describing the method is available here.
ORTHOFIND first identifies all strict sequence homologues with a BLAST search against SwissProt v50.6 using an e-value threshold of 10-2. It then removes all paralogues using a functional filter where SwissProt annotations are compared. Finally, it chooses the best functional match from each species to identify the functionally equivalent protein in each species.
To ORTHOFIND a particular SwissProt ID, enter it in the form on the right. Select what kind of proteins you are interested in. For example, if you don't want to return fragmented homo-orthologues, de-select 'Sequence fragments'. 'Unreliable proteins' have are described as hypothetical, probable, putative, -like, or as a homolog of another protein in the SwissProt description field. By de-selecting 'Sequence matches', any homo-orthologous assignments made on the basis of sequence matching are eliminated from the results displayed.
A full XML output of the results is available. Download it here (right click and "save as").