"Get away from her you BITCH!"
Who doesn't know that line? If you don't then RUN, don't walk, RUN to the nearest store that will carry this, buy it and then play it over and over again until you have the lines of the movie burned into your brain for life!
A movie that has stood the test of time. It's got action, suspense and some AWESOME one liners. Recently they released a version that carries an additional 17 minutes of play time, including some scenes that flesh out what the people on the Alien planet were living like before the attack.
A great movie to have playing in the background while you're out killing stuff.