Browser scroll - do something

gistfile1.js

var scrolled, $w = $(window);

$w.on('scroll', function() {
    scrolled = true;
});

window.scroll_timeout = setInterval(doSomething, 100);

function doSomething() {
    if (!scrolled) {
        return;
    }

    scrolled = false;

    console.log($w.scrollTop());
    if ($w.scrollTop() > 250) {
        console.log('CHEGOU!!!');

        $w.off('scroll');

        clearTimeout(window.scroll_timeout);
    }
}