Sooo, to be honest I didn't like Alien nearly as much as I thought I would, at least the second half of it. I find it degenerates more into a generic action/horror movie after the famous scene of the Alien's burst through Kane's chest. To be fair, some of that probably has something to do with sequences of other, later movies being in a large part inspired by this movie, but I just lost considerable amounts of interest through the latter part of it.
What I can only agree with however are the, especially for the time, amazing visual effects and set. The alien ship, and the cave underneath are just stunning, and I don't think it would even with modern technology be possible to make the facehugger look more realistic than it does here.
All in all I'm probably with PostIronic on this one, I don't love the film in particular, but it's defenitely among the Sci-Fi greats, and deserving of its place in movie history.