This is the Lego version of the Caterpillar P-5000 Powered Work Loader, also known as a Power Loader. It looks like Ripley is ready to fight, rather than power load space stuff. This little build is the creation of Andreas Lenander. Who creatively used the Lego fence piece for the cage. Also check out the joysticks and the tiny feet. Just be advised that an Alien is not included.
You can find more about Ellen Ripley’s Power Loader over here: https://www.flickr.com/photos/124068149@N02/32136566840/
Check out this even smaller Lego Power Loader here: http://legogenre.com/cutest-lego-mini-power-loader-aliens/