This script fills the matrix authentication of portal.titech.ac.jp. You can use this as a bookmarklet.

fill_matrix.js

var matrix = {
    A: ['I','U','U','A','I','Y','F'],
    B: ['Z','N','C','C','U','O','G'],
    C: ['V','A','K','I','V','R','B'],
    D: ['N','S','R','U','H','A','I'],
    E: ['N','M','R','T','E','A','P'],
    F: ['E','B','O','P','L','K','P'],
    G: ['X','L','O','M','O','I','D'],
    H: ['A','E','L','O','H','A','E'],
    I: ['Y','I','X','T','J','F','G'],
    J: ['O','N','J','X','W','E','G']
};// Sample
var f = document.forms[0];
var es = [f.elements['message3'],f.elements['message4'],f.elements['message5']];
function get(node){ return node.parentNode.parentNode.childNodes[1].textContent; };
var cs = [get(es[0]),get(es[1]),get(es[2])];
function get_m(s){
    var cn = s.split(",");
    return matrix[cn[0][1]][parseInt(cn[1][0])-1];
};
var ms = [get_m(cs[0]),get_m(cs[1]),get_m(cs[2])];
es[0].value = ms[0];es[1].value = ms[1];es[2].value = ms[2];undefined;