Very usefull plugin for KnockoutJS

Map that plain JavaScript object into a view model with the appropriate observables!

More info : http://knockoutjs.com/documentation/plugins-mapping.html
Download : https://github.com/SteveSanderson/knockout.mapping/tree/master/build/output

Set a html checkbox to indeterminate state

var checkbox = document.getElementById('myCheckbox');
checkbox.indeterminate = true;