... but here we go...
The problem with the aliens spawning us argument is that it just shifts the problem to somewhere else - how did the aliens come into being? The really big questions remain - why does anything exist at all? why does life exist? what is consciousness and how does it relate to matter?
I have very personal answers to these questions which could be considered "religious" - but I don't like trying to express them too much because in doing so I feel they lose some meaning in the process of trying to explain them to others.
Some atheists I know (definitely not all) adopt an air of smugness about not believing which really isn't justified IMHO - there's a lack of acknowledgement about current and potential limits to scientific investigation and modelling of the physical world and what inferences can be gained from that. Two books I'd highly recommend which cover these ideas from a scientific perspective (as in, the limits of our understanding) are Pi in the Sky and Theories of Everything, both by John D Barrow who's a British astrophysicist.
Which isn't to say that I don't think people should be atheists - if that's the explanation for existence you prefer, then fair enough. But if your worldview is meant to be based on logic and reason you should acknowledge that logic and reason have limits as well.
Ultimately the only philosophical position which doesn't appear to rest on some assumptions about the world is solipsism. The only thing you can be sure of is that "you" are experiencing something.
I also think anyone can believe anything they want to as long as they don't use that as a justification to hurt or control anyone else, or to openly express hate towards others (Taliban, Westboro Baptist Church, etc). And no one should dismiss or denigrate anyone for what they believe as long as the people who believe that aren't trying to hurt or control anyone.
