Yes, if you think of faith and proof as a sort of continuum where you can have varying amounts of each (Faith + Proof = 100%). Think about it this way: I believe that the sun will rise tomorrow. Why? Well, I have over 23 years of firsthand evidence that the sun rises on a daily basis. In fact, in all of recorded history it has never failed to do so. I’d say that’s a pretty good track record. So logic (plus a basic knowledge of physics and astronomy) tells me that it’s likely to rise again tomorrow. I don’t have absolute proof that this will be the case, in the sense that I’m not psychic, but I have about 99.9% solid evidence. So I only need about 0.01% faith that nothing astronomical will happen before tomorrow’s regularly scheduled sunrise.

Now, if I were to assert that tomorrow we’d all wake up to a giant glowing purple bunny looming over the horizon, or that the earth would suddenly go careening off its axis into another galaxy, I’d be seriously lacking in either evidence or logic to support those claims. I would need a whole lot of faith to replace the big gaping hole in my proof. (Sound familiar?)

So since I firmly believe that god does NOT exist, yet I have no absolute proof, you could say that some “faith” is required in the sense you describe it. But my beliefs require a lot less faith than a theist’s. So to answer your second question…

“Can you have just as much faith in the nonexistence of [god] than in the existence of it?”

No.

I do have faith in those around me though. I believe in the ability of my friends to do good things even without having to see proof of such.

I have faith, just not in conjunction with any religious/non-religious beliefs.

If faith is the belief in something that cannot be proven, then would it be right to say that we have faith that there is no God? I mean, we can’t really prove it right? Can you have just as much faith in the nonexistence of something than in the existence of it? If this is true, then when people come up to us and say we have no faith, we can promptly reply with “Actually, I have faith that everything you are preaching is a load of horse shit.”