At any given moment, millions of scientists, researchers, programmers and others, are working for the common good. Some have selfish motivations, and others may not understand the import of their work but in the end we may all benefit from their endeavors. Since we do not know what the future holds, it is difficult to accurately predict which projects will turn out to be the most significant; it is likely that many ventures will end in failure, and in retrospect, we may even be surprised that some were even undertaken. We can, however, uncover some leading candidates for most critical projects currently underway.
Medicine - We'll start with the most obvious. Medical improvements can benefit all of us, either directly or indirectly. Cures to epidemics, or new medical therapies, perhaps genetic, can improve the quality of our lives. A cure for cancer or AIDS can end up saving millions of human lives and elevating the quality of life for millions more. Perhaps the most important work in this area is being performed by those trying to come up with new and faster methods to cure communicable diseases; there are many teams preemptively working on systems and techniques to quickly determine the root causes of new diseases and to devise the plans to eradicate them. All sorts of new diseases are arising in our increasingly populous and intermingling societies. If one of these diseases were to get out of control and develop into a pandemic, the researchers who figure out how to hinder them may become the heroes of the future.
Diplomacy - The population of our planet has been steadily increasing, but living space and available natural resources remain finite. Tensions are likely to flare, and there are many people working to make sure that the various power structures in the world will function cohesively in the future. Major discord between competing entities can lead to unprecedented harm. Those that are working to eradicate terrorism at its source, and those that work toward international accord may be involved in today's most important work.
Spiritual - There are many people that dismiss the importance of physical practicalities of our lives, and focus their efforts on more grandiose ends such as personal fulfillment, enlightenment and moral living. They urge us to strive for meaningful lives as opposed to merely comfortable ones; others try to shift attention to the afterlife as opposed to the here and now. It is possible that the work done in promoting these spiritual ends will accomplish the most for humanity in the long run.
Alternative Energy - Just a few hundred years ago, the issue of energy was mostly irrelevant. People collected wood for cooking and heat, and maybe used sunlight to warm water. Modern society, however, is entirely different, and much of what we do is directly or indirectly based on energy. Energy is used for transportation, industrial production, communications - even the harvesting and transportation of fruits and vegetables relies on a surprising amount of energy.
As the amount of available petroleum begins to dwindle and become more expensive, our modern lives will require an alternative source of energy. Will it be wind, solar, nuclear, hydrogen, or some new unforeseen technology? It is difficult to predict, but it is clear that without some significant advances in this area, the future could be unimaginably, and perhaps tragically different than the present.
Nanotechnology - Nanotech is a budding field, and it is unclear if it will pan out. The promise of atomic-sized "machines" and "nanobots," however, is high. Will these technologies yield super-materials or lead to great strides in medical science: time will tell.
Computing, Internet and Artificial Intelligence - As processing power improves, the functionality and value of computers tends to increase significantly. The best computers of just a decade ago could not even handle tasks that the average desktop computer now handles with ease. The networking of these computers has expanded the possibilities even further. Computing and the internet has already changed many of our lives. We plan trips, research products, and explore our history in entirely new and more efficient ways. It seems clear, however, that the impact of the internet has just begun its influence on our lives. As processing power continues to improve, and as the collaboration afforded by the internet evolves, the impact is likely to skyrocket. With this increasing computing power of a unimaginably extensive network, comes the possibility of improving artificial intelligence. If all of this work culminates in a technological singularity, then perhaps all of the other projects listed in this article will seem insignificant. Aside from a singularity, however, improvements in computing is certain to speed technological advancement in all fields.
Robotics - The field of robotics has been around for many years, and although there have been plenty of advancements, robots do not seem to affect our daily lives in any significant way. Of course robots make great toys, many are used in manufacturing facilities, and others are used for sea exploration or bomb detonation. It is likely, however, that all of this will change. As computing power improves and becomes less expensive, robots are given the 'brains' that they need to become very useful. What happens to society if you introduce relatively inexpensive and relatively intelligent robots that can perform many of the mundane tasks that take up much of our days. They work without complaint, without rest, and are prone to fewer errors. The result can be highly disruptive, especially if the new robot class puts huge swaths of people into the unemployment line.
Space Travel - To some, this may be the most perplexing entry on this list. Suppose that the medical researchers described above are not able to stave off some future viral plague. Or imagine the nightmare scenario of a huge asteroid colliding with earth. What if drastic climate change ends up rendering our planet inhospitable to any form of life. Although it is statistically unlikely for any of these disasters to occur anytime soon, the space industry may be laying the groundwork for species-saving colonies in space. In other words, if we can eventually get enough people to live in space, then perhaps we can protect our genes and our species from global catastrophe.
It is clear that some important issues were omitted from the list above, but it was not intended to be exhaustive. It may turn out that the most important work isn't even on the radar right now. What is clear, is that although we are faced with unprecedented issues and problems, we have the technology and capacity to solve them; it is certainly a very exciting time to be alive!