Some... play along, trying to get their own stuff done on the side. Others... are happy to have a good place where they can surf the net the whole day, while pretending to be scientists. Some of my collegues are completely clueless... but being generally friendly goes a long way.

Congratulations! Your training is nearly complete! Welcome to the ranks of the enlightened! ;)

Your essay is pretty comprehensive and one can't really do it justice in less than an entire evening in a bar. But I'll offer some random observations.

You need to focus on a concrete goal. "Research is my main dream" is not a goal: It's a not even a real mission statement. "Get out of grad school with my degree" is a goal. "Get out of grad school right now, degree or no degree" is a goal. "Hang out in grad school while starting three YC companies" is a goal. "Go skiing every weekend until they kick me out of grad school, then get an industry job" is a goal. None of these is necessarily better than another; it depends on you.

You need to learn how a research career plays out in the real world. No, scratch that -- you've obviously learned it; you need to take a vacation from academia long enough to accept it. ;) The fact is: if the reviewers are happy, and the funding is good, you're an academic success. That's the goal of academic research, and if it disgusts you, you should get out of academia permanently. Because, frankly: "Finding elegant solutions to difficult problems that have wide-reaching implications" is almost uncorrelated to success in academia. You can be nearly as successful, with much less risk, by publishing over-complicated solutions to easy problems, or non-solutions to difficult problems, or incomprehensible solutions to niche problems. And you will find that the overwhelming majority of your colleagues spend most of their time on one of these paths, because they require less risk and less time, which leaves more time to go to conferences and write grant proposals and supervise students and curry favor with your colleagues and deliver lectures and all the other things that comprise actual day-to-day life in most academic jobs.

You need to realize that you are probably a very successful grad student. You can't tell right now, because you're still absorbing the truth: Most research projects are failures. That's what research is all about: Failing, over and over, but taking copious notes each time so that you have an idea of why you failed. As a student, such failure matters very little. My own Ph.D. thesis was a big catalog of various mistakes, ranging from small-scale implementation difficulties to grand-scale theoretical misconceptions that took three generations of grad students to unravel. And it went over just fine. People love reading about other people's learning experiences. It helps them learn what to avoid.

I'll repeat this, because it's important: You're a student. Nobody expects you to actually solve an earth-shattering problem. They expect you to do a bunch of work, help write some grants, write up something that your committee agrees is novel (but not necessarily earth-shattering) and then graduate and go work on something else. Which you should do. Unless you decide to just start working on something else right away, which would also be good.

Before this post gets any more Steve-Yeggesque: Yes, you can do research outside of academia. (You sound like a comp sci student, so take a moment to pity those EEs whose graduate work requires millions of dollars of capital equipment and a sizeable staff of techs. And even we can find ways to do research outside of academia.) You will find that it's much harder to get recognition for your work outside of the academy, but you have to ask: Are you in research for the adulation and the money and the girls, or are you in it for pleasure? Consider that many of the most successful discoveries were made by (what were then regarded as) semi-obscure cranks. (Think: Mendel.) Consider the delightful personal pleasures that crackpottery has to offer.

And, finally, I would note that if industry pays 30-40% more than your current job, that means you could work 60% of a full week at an industry job and still have time left over for your side projects.