Can I use jQuery to check whether at least one checkbox is checked?

if(jQuery('#frmTest input[type=checkbox]:checked').length) { … }

$('#frmTest input:checked').length > 0

$("#frmTest").submit(function(){
    var checked = $("#frmText input:checked").length > 0;
    if (!checked){
        alert("Please check at least one checkbox");
        return false;
    }
});