Presentation of binary relations

Given is a binary relation R as a subset of S x S, with a simple
representation in XML (e.g. <R><E><s1>x</s1><s2>y</s2></E>...</R>).
Clearly this can be represented as an HTML table, with rows and
columns labelled with si and 'x' in the table cells where appropriate
(but I'd accept any other generally available presentation technique).

A list of <si> elements in the desired order for row/column labels can
be provided.

Now this seems to be a pretty mundane task, and I wonder whether
anybody has/knows of such a simple *existing* transformation?

Thanks
Wolfgang