Numeric only input using jQuery

This is a nifty little jquery snippet I use all the time for numeric only text boxes.

$(function () {
    $(".numeric").live("keydown", function (e) {
        if (e.keyCode != 46 && e.keyCode != 8) {
            if (e.keyCode < 48 || e.keyCode > 57) {
                e.preventDefault();
            }
        }
    });
});