I refuse to beleive that Earth is the only planet that supports life in the entire universe, if that is true not only would sapce become BORING but that would mean the young earth creationists are right about something. And they must NEVER, EVER be right about ANYTHING.
Anyway.
We've discovered planets that are capable of supporting life, or at least have 'earth like conditons' so it's not hard to beleive that planets out there can support life, there's the possibility of the planet Gliese 581 c for example. Lest we forget the 'water on mars' idea. Some people might think Earth was a fluke but honestly I think the sheer number of planets in the universe have to count for something. Earth had the right conditions I beleive for life, atmopshere, gravity, water and sunlight. Those are according to most scientists the key things needed to allow life to gradually evolve, abiogenesis. The way I see it, there is no way that there can only be ONE sun, there have to be infinite numbers of them throughout the universe, it's impossible to think there's only one. Life forms HAVE to exist out there, maybe even just in the early stages of evolution just like Earth was a few billion years back.
I mean I hear they've found evidence of Micro organisms on Mars and so it's at least a start. For all we know there could be billions of planets with life on them, of all kinds. Maybe even civilisations too, I refuse to believe Earth is alone. It simply cannot be, big universe must be life out there somewhere.
I reckon that yeah maybe out there there exist planets with giant alien monsters. Intelligent civilisations of sophisticated aliens, the Sangheli warships and if we are really lucky some hot alien chicks.
Maybe there's life out there right now on other planets having similar conversations on their forums right now wondering if there is indeed life out there.
Actually I just found out that scientist got a picture of what they beleive to be fossilised bacteria on a meteorite from Mars. I'd post the picture but I don't know how, could someone maybe explain how you do it?
In the meantime look up Extraterrestrial life on Wikipedia, go to the part about direct search, it's there.