Compared to more established sciences, I agree that it is somewhat disappointing to think of how little neuroscience has really given us. I view it as one of the last frontiers of scientific investigation. The relatively recent development of functional brain imaging has opened up a lot of possibilities, and I am hopeful that soon we can begin tackling the bigger questions.

I have to say that I am a little confused at your comment, "we don't even know how neural networks work." The entire point of neural networks (at least the way that I understand it - which I admit may be flawed) is that we do understand how they work, and that this fact allows us to learn a thing or two about how the cognitive processes that they emulate work. Whereas we cannot break open the black box that is the human mind and examine how it is functioning (at least not currently, or probably any time soon), we can do just that with neural networks and other computational models. So if we have a computational model that appears to mimic human cognition, we can infer that they must be utilizing similar processes. Is this not the way that you understand neural networks?

On a side note: I find the analogy of using "brute force" to understand brain functioning to be very amusing. I have never viewed science as a "brute force" sort of process, but to each his own, I guess.