Below you can find various projects using the XMCDA standard to access MCDA data.
The diviz software;
The XMCDA web-services;
The kappalab R library through the XMCDA R library;
The Python digraphs module for Rubis;
The J-MCDA project (Helping develop MCDA methods in Java).
Have also a look at the currently existing XMCDA libraries.