XML To Any uses XSLT 1.0 to do non-schema aware transformation of incoming XML source to a different format. Currently JSON, JSON-P, Lua, Verbose Lua formats are supported.

There is a XSLT 1.0 processing library available for every major language e.g.  For Java. PHP is used here just for demonstration purposes.

The query parameters are -

    format - Desired format. luax (Lua Verbose), lua (Lua Compact), json, jsonp (JSON with padding).
    callback - Callback function name for jsonp format.
    url - URL of the XML source.
    decimalSupported - This is not a query parameter but a transformer parameter. Currently it is set to 'no'. If set to 'yes', it will not put decimal numbers in quotes. 
    
PS- I did this to try out iPhone Wax.