Ok, so this is pretty much the same as my Jurassic Park in 1080p thread. I have this movie on my computer in 720p from an HDTV rip, and I can get some good screecaps if anyone needs them. It's 720, not 1080 like Jurassic Park, but they are still pretty large, and sharp. As with JP, Alien has yet to see a commerical HD release, so I thought some people might find this useful.
Here are a few examples.