I believe that everyone has a vocational calling. (In fact, that's a little redundant, since the word "vocation" means "calling" in its etymology.) That doesn't mean that someone must work at the same job or even in the same area all their lives. One's calling can change. But, generally speaking, I believe that God has made each of us with certain natural abilities as well as inclinations that help match us up with certain tasks. In addition, God is in control of the circumstances of all our individual lives, so that opportunities come our way (or don't come our way) that providentially steer us in certain directions. The process of figuring all this out may in some cases be rather grueling. It may be particularly hard when we aren't aware that the process is going on or don't acknowledge it. The best way to discern our calling is to understand a little about the process behind it -- that God is in control of it, that we are answerable to him, and that he has provided certain steps for us to gather wisdom to make such a decision.
In general, man's calling is to "subdue the earth". Basically, this means learning about the laws of nature, the resources that are available, etc., and putting these things to use for good purposes. This is such an innate part of us as humans that we tend to pursue these ends even if it doesn't flow out of a "philosophy" of work. One of the really exciting things about being an engineer is that it's so easy to see how this calling fits into the general responsibility that man has to subdue the earth. An engineer is one of the few callings in which one can see the process as a whole, albeit only a small cross-section at that. So, for an engineer, it's a lot easier than some callings to be motivated by the vision of being part of this process.
The bottom line here is that God created work to be a good thing. This flies in the face of our culture's view of work. In our culture, leisure is the goal, and work is often just a means to achieve leisure or a necessary evil to sustain life. On the other hand, work is sometimes made into a god. One's job performance becomes the chief measure of the value of a person. The Christian view provides a fine balance between these extremes. Leisure is subordinate in importance to work. Since work is the more basic calling, leisure takes a back seat in importance and in the potential for satisfaction. Because we spend the majority of our waking hours working, it is comforting to know that work has a greater potential for providing deep, long-lasting satisfaction. On the other hand, we are guarded from making work an idol by acknowledging that work is a stewardship from God. We must give work the priority that God assigns to it but not a higher priority.
However, there is a major wrinkle in all this. Because of man's refusal to acknowledge God and man's rebellion against him, God has cursed the fruit of our labor with "thorns and thistles". All is not as it was in God's original blueprint. Work is subject to failure and frustration, and in some cases this experience overwhelms the satisfaction that should flow from working hard. So work is a mixed bag. And this applies to all work, whether it be research or digging ditches. No work is free from frustration and failure.
All of this combined gives a very realistic picture of work. Since work is basically a good thing, we should commit ourselves to working hard and seek to find satisfaction in it. In fact, we will find the greatest possible satisfaction when we commit ourselves to the role that God has designed us for and assigned to us. But since work has a cursed aspect to it, we should expect that frustration will be a regular part of our job experience. That shouldn't cause us to give up though or to substitute leisure as our primary outlet for fulfillment.
The tricky part is that frustration can be the result of missing the calling for which we are suited, or it can simply be the irreducible difficulties that are part of any job. Determining which one is the case is not always easy. But I believe that the Christian has resources available to him for making this determination that aren't available to others.
My article, "The Spirituality of Work", goes into more detail on the Christian view of work.