I think it would be strange to think that there is not life in other parts of the galaxy when you think of how many planets there are. But when you consider the scale of the galaxy it seems like it doesn't really matter much. I mean it's 100,000 ly across, nothing can travel those distances except light.

I am unaware of any life found on Mars. If single celled life forms have been found on Mars, then extra terrrestrial life is not only possible, it would be a fact. Mars is extraterrestrial and single celled life forms are life.

Capable of suporting life is a long way from life having formed, unless the process of the formation of life is much more probable in a supportive environment than most tend to think. 

Same can be said for god, angels, ghosts, fairies, bigfoot like creatures. People see lots of things that there is not sufficient reason to believe actually exist.

I would agree that a possibility exists for extrateresstrial life to exist as iIdon't see the idea of extraterrestrial life as being self contradictory in any way, but I think that with the knowledge I possess at this time there is not sufficient evidence for me to believe that it does exist.

any discussion of extraterrestrial life has to be narrowed down into one of the 3 following categories:

1) Is there life elsewhere in the universe?  Looking at it rationally, the answer is "probably".  given the number of stars in each galaxy, multiplied by the number of galaxies, it is nearly a statistical certainty

 2) Is there intelligent life elsewhere in the universe?  like #1, the answer is "probably".  (both #1 and #2 can also be broken down into "currently" and "ever&quot.  THe Drake equation deals with this question.

http://en.wikipedia.org/wiki/Drake_equation

3) Has intelligent extraterrestrial life visted earth.  This is where things get murky. there is definately a lack of evidence (conspiracy theories not withstanding).  However, the question I like to ponder is "If humans decided to try to observe a held of antelopes in a remote region that had never encountered humans, and if those people were determined to be unobtrusive and not let those antelope know they were ever there, how would the antelopes (a) comprehend the fleeting glimpses of their observers, (b) prove that people were watching them?" 

 as for personal experience, my only "encounter" was driving down a desolate interstate at night, and seeing lights that (a) aren't supposed to be there, and (b)  don't fit conventional explanations.

I am not aware of ANY life being discovered on Mars, signle-celled, fossilized or otherwise. I do think it may have existed there or could even still be there now, deep in the soil under the ice caps, but it has NOT been confirmed to my knowledge.

Europa and Titan are other remote possibilites for life. It'll be centuries before we have the capability of doing a proper exploration, and by that point we may have simply contaminated those worlds with our own biological refuse that took root - though the evolutionary considerations would still be staggering.

 Personally, when I look at the sky, in my heart I think that it would be an awful waste of space for nobody else to be out there - Sagan actually shared the same sentiments in his book "Contact". Still, if there is intelligent life out there, I doubt we will ever find one another, and if we did find it, I agree with Hawking that we ought to be wary of it, as we'll likely appear as ants to them. At any rate, I'll be voting for Kodos

I actually think the occurance of intellegent life in the universe is much, much lower than the proponents tout - still, I'm not really basing that on much more than they are, it's just a gut feeling, really. 

Still, I think it is relatively possible that we will find evidence or at least past evidence of alien life in our own solar system - it simply won't be little green men, but little gree algae.