Todd Ditchendorf has released XML Nanny 1.1, a free-as-in-beer Mac OS X "tool that provides an Aqua interface for checking XHTML and XML documents for Well-Formedness and Validity either locally or across the network." Version 1.1 adds support for W3C XML Schemas, improves error messages, and reports multiple errors in a single document. XML Nanny is based on Xerces-C.