(Original post by ThisIsTheLife)
I wouldn't really call the first two ATHEIST symbols. They're symbols of evolution, and evolution certainly does fly in the face of certain aspects of religion, and I suppose the symbol does allude to this by the fact that it's the Christian fish with legs and tools. So they are symbols that indicate that in the "evolution vs creationism" debate, you come down on the side of evolution (and sensibly so).
But then evolution flies in the face of MANY ideas, and atheism is NOT the same as "flying in the face of religion/creationism".
So if you're pro-evolution, then as a pro-evolutionist, I would say that the first two would be appropriate... but they are not "atheist" symbols, and there are plenty of religious people who believe in evolution - many of them prominent biologists and evolutionary theorists who down on evolution side of the evolution/creatinionism argument, and they would be just as happy to have that tattoo or have that as a bumper sticker or something as you are, so I don't really think it says "ATHEIST" like you think it does...
As for the last one. Well yes, it certainly says "ATHEIST", but I'm a bit perplexed as to why you'd want to be identified by that symbol. I'm an atheist too, which means I don't believe in any form of deity. But there's LOTS of things I don't believe in, and I'm hardly going to get tattoos representing my non-belief in fairies, mole people or the effectiveness of homeopathy... or anything else for that matter.
I am an atheist, and I love a good debate with a religious person. But I think to identify yourself by the thing(s) you don't believe in is a bit absurd in my honest opinion. I would identify myself as a rationalist, but I don't necessarily thing that the A symbol represents that - there are plenty of atheists who operate under the A symbol who have arrived at their atheist conclusions in completely irrational manners. Even if they're right, they don't know why they're right, and they're right for all the wrong reasons.
So for me, I'd ditch the last one because it's a bit ludicrous, and I'd opt for one of the first two, but only as a pro evolutionist, and not as an atheist.
But then, say in 30-40 years time the creationism vs evolution has died down and everybody thinks creationism is ludicrous. Well, at that point you'll be wearing a symbol of a controversy that no longer exists - and there'll probably be plenty of new controversies that would be more apt to cover yourself.
Personally, I'd get something that represents rationalism in general. Rationalism will always be valid and will never be dated. It stands for all sorts of things in individual debates, but it's always consistent, and you know that you don't mind being identified with fellow rationalists.
Just my 2 cents.