In our experience, AvP was one of the better combinations of practical and digital effects. To accomplish the Queen Alien's egg laying chamber scenes, for instance, we created a cable articulated 1/3 scale puppet Queen and a hand puppeted Ovipositor. Digital warriors swarmed her to set her free. We also tested a 1/4 scale Queen rod puppet. This video shows us giving it a first go. At this point it was mostly just wiggling, but you gotta start somewhere! Courtesy of ADI.