In stock Android, when you drag the notification drawer down, you can tap the button in the upper right to access quick settings like Wi-Fi, data, brightness and more. If you want to jump straight to these settings, you can drag the notification drawer down with two fingers.
Just place two fingers on the top of your screen and drag down -- that's all it takes. You'll go straight to the Quick Settings panel without having to tap the button in the upper right, which is pretty handy. This is for 4.3 and above -- if you're on 4.2, you'll want to drag with a single finger on the far right side of the drawer.
Of course, if you root and install something like GravityBox, you can have it show up automatically when the notification drawer is empty, or have it show up when you drag on either edge of the drawer.