There have been many threads regarding this issue.  I believe a few members have also written rather detailed essays on this too, though I could be wrong about that. 

Links?

 Healing an amputee would be a good start.

http://www.whydoesgodhateamputees.com/

What would it take for you to believe in Vishnu?

the question i would have to ask is why does it matter to you? even if god appeared before me and spoke to me and showed me miracles, i still wouldn't bow to him.

there's a list a mile long of horrific events and tragedies that, if god did indeed exist, he should have prevented.  at the absolute minimum god should have stopped his own priests from sexually abusing children. why would i ever worship a supposedly all knowing, all seeing, all powerful deity that sat idly by while a child was being raped by one of his own servants in one his own churches?

it's disgusting that christians continue pray to "god" after these events came to light. by doing so they are essentially endorsing a supreme pedophyle.

god, would convince me of the existence of god.  that's about it, b/c if it was god he would know how to convince me.

Why fill the "gaps" with anything? "I don't know" is a valid, acceptable answer.

I can tell you what WOULD NOT convince me of god... "gaps". Just because there are these so-called gaps does not mean god is there. 

No offense, capn, but you know that the "god of the gaps" is just a variation on a logical fallacy called argument from ignorance, right?

I mean, you're admitting, clear as the nose on my face, that you believe in god because you accept a logical fallacy.

And you wonder why we don't believe?

Nevertheless, you ask a legitimate question, and I believe you do deserve better than a socratic answer.

Naturally, you've heard the saying, "Extraordinary claims require extraordinary proof." Well, in a way, that should be self-evident. To put it another way, nothing that could happen naturally is evidence of god. Nothing. Period. Ever. What would be evidence? Something that so completely defied science that it could only have happened illogically. A documented, medically verified account of a priest praying for a double amputee who immediately grew both legs back in less than a minute... that would be a damn good start. Or, maybe if all the guns and rockets in the entire world started exploding into showers of daisies instead of killing people, and a big banner spread across the sky and said, "I am god, and I will not allow you to kill each other again." That would be pretty good proof.

Here's something else you have to consider, capn. Even if someone documents something so irrefutable that it can only point to the existence of a supernatural being, how do you know which one it is unless he happens to leave a signed copy of a pay stub? How do you know it's not Allah? Or, heaven forbid, maybe everybody's had it wrong all along, and nobody's ever heard of this god before?! Maybe god doesn't care that people believe in lots of other deities. Maybe earth is just one bacterial culture in a line of cosmic petri dishes a billion galaxies long, and god hasn't bothered to check in for the last 30,000 years since we learned to make axes!

The point is, capn, that your god, just like everybody else's god, is believed in out of faith, tradition, and ignorance. So, what we come back to is that believing in a god is something that just doesn't make much sense. I'm happy to answer your question of what it would take, even though there's a great possibility that even now, you are shaking your head, wondering why I couldn't just answer you with a straight answer.

That's the thing. This is a completely honest, straight answer. It would take, literally, a miracle! Something that absolutely could not happen naturally.

It's not a dumb question to ask, capn. It does, however, beg the question.... "Why don't you disbelieve in your god, since the concept is nonsensical?"

And... in defense of other posters, it does beg the question, "What would it take for you to disbelieve?"

I think if you examine things critically, you will find a double standard, if not hypocricy. In other words, I, and most other atheists are perfectly willing to believe in anything that is proven to exist. (Or, disbelieve in something for which there is no evidence! I suspect few people on this board believe in the Loch Ness Monster, for instance.) However, you are unwilling to even consider the possibility that you are mistaken and that your god doesn't exist. Why? It's different for everybody, but most commonly, it's fear and ignorance.

Have you read Darwin? What about Sagan, or Hawkings? Do you know what the evidence for evolution is? Really... do you know? Have you ever studied logic? Even a little? Have you ever tried to work out your belief in god as a logical equation? Are you afraid to try?

"..but doesn't it make my believe as rational as yours?"

i don't think there's anything remotely rational about belief in a higher power. if an adult friend told you they sincerely believed that a little fairy went around exchanging coins for children's teeth, would you say that's completely rational? or would you recommend couseling? 

Actually, it's intellectually dishonest. The problem with gaps is that you could fill them with anything, and as long as there is a lack of knowledge, you can't be shown wrong. Why not fill the gaps with a great wizard, or alien warlords? To claim that you have an answer to a question that cannot yet be answered is just a lie. The only thing to claim when knowledge fails is 'I don't know'.

Try 12 minutes ago... 

Since it's impossible to disprove something, especially an idea outlined as something inherently unfalsifiable, literally every proposition ever conceived joins the “god of the gaps” in the pantheon of indeterminate possibilities. It's not a particularly satisfying position.

I'd first need to understand what God is and then why it is necessary to believe in him. It's difficult to talk about what would be evidence of God until we understand exactly what God is.

It is my suspicion that most theists don't really understand what they mean by the word 'God' either...

I'd say he'd need to drop out of the sky and right into my backyard while I'm having my morning smoke.  Yeah, that'd do it for me.

Honestly, anything would prove the existance of god to me because all I'm getting right now is the alternative: nothing. 

No, in fact it doesn't.  

Well there's compression of continental plates causing mountains to move.

ahhh crap.