I have not seen 「The Matrix」 (dislike Keanu Reeves), but I understand that it involves aliens somehow getting utility out of people being asleep and dreaming. My suggestion is that were those same aliens to really need whatever that is so much (physics modeling? quick bayesian decision evaluation? virtual reality? storytelling?), they would be well-advised to consider using cats instead. They're probably easier to feed, less likely to ninja your plan (well, maybe?), they live in a much more exciting mental world, and they're a lot more compact.
It might not make as exciting a movie though (although I would wager my cats have more personality and interestingness than Keanu Reeves).