Simple, easy to use console replacement script for use in JsFiddle...

console.js

if (typeof($) === 'undefined') {
	alert('jquery is required');
}
$("body").append($('<div id="console-log"></div>').css({
	backgroundColor:'black',
	color:'#33FF00',
	padding:3
}));

var consoleLineCss = {
    fontFamily: 'monospace',
    margin: 2,
    marginBottom:10,
    padding:2
};
if (!window._console) {
    window._console = console;
}
console = {
    group: function(nm) {
        _console.group(nm);
    },
    groupCollapsed: function(nm) {
        _console.groupCollapsed(nm);
    },
    groupEnd: function() {
        _console.groupEnd();
    },
    table: function(data) {
    	_console.table(data);
    },
    log: function (text, obj) {
    	_console.log(text,obj);
        var objText = obj ? JSON.stringify(obj) : "";
        $("#console-log").append(
        	$("<p/>")
        	.html("<b>" + text + "</b> " + objText)
        	.css(consoleLineCss));
    },
    reset: function() { $("#console-log").html(""); }
};
console.reset();