a.k.a. The Squat Thrust
Benefits: Puts her in control; maintains intimacy.
Place pillows behind your back and sit on the bed with legs outstretched. She straddles your waist, feet on the bed. She then bends her knees to lower herself onto you, using one hand to direct your penis in. Just by pressing on the balls of her feet and releasing, she can raise and lower herself on your shaft as slowly or quickly as she pleases.
Now try this: From this position, you both lie back into the Spider position or its more challenging variation The X.