For months we've hosted the debate here at Techland, and after much consideration, deliberation (and surprisingly few insults), here they are: The five underrated sci-fi movie masterpieces. (If you're looking for Steven Spielberg's A.I. by the way, you're looking in the wrong place - see my top 10 sci-fi films of the last decade instead)

Watch a few of the clips above, then read our full appraisals and join in on the debate. Just click here.