Can anyone direct me to a simple (preferably open source) tool for searching various tags or areas within an EAD finding aid? I'm envisioning something that works somewhat like an OPAC interface, with fields for searching by creator, title, date, controlled vocabulary, full-text keyword, provenance, <unitid>, etc.

I am currently working on a very simple and straightforward such tool in Perl using CGI. It functions (to simplify significantly) by generating XSLT documents which contain tests for the queries input by the user, which are then applied to each EAD document within a specified filepath. Am I reinventing the wheel? If not, would there be any interest in such a program if I were to generalize it enough that it could be integrated with other institutions' web interfaces?