Using Require.js without data-main

Yep, take a look at the documentation: http://requirejs.org/docs/api.html#config

You need to call require.config() and set baseUrl. Based on your example:

<script src="https://stackoverflow.com/questions/12865630/scripts/require.js"></script>
<script>
    require.config({
        baseUrl: "scripts"
    });

    require( [ /*...*/ ], function(  /*...*/ ) {
        /*...*/
    });
</script>