Some aspects of transcendentalism can be applied in today's society, while some others cannot because of social and economic conditions different from the time of Thoreau.
Transcendentalists believed a goal was to have Utopia in the present in the U.S. instead of in another world. They also believed that you should do your own thing only if it does not infringe on others. I think that almost everything we do affects or infringes upon someone else in a world with such a great population. The idea of Utopia is very subjective; it is different for every person.
They also believed in the Jeffersonian Philosophy that each generation should only be concerned with itself. They also believed that if each generation were to improve on the work of the last generation, a perfect world would eventually be created. I think this does not fit into today's society because there are many aspects that, if we were to take the option to help our generation, the later generations would pay. An example of this would be providing jobs for a strip-mining project to help the current generation's economy, while it destroys the environment for later generations. Transcendentalist's belief of adding onto the previous generations work would not work if each generation, to help itself, is destroying the world.
Back in the 1800s, issues like slavery and the transfer of political power were decided by having wars, as shown by the revolutionary war and the Mexican Revolution. Today, these decisions are often controlled by special interest groups who lobby to make the laws suit their special interest. Transcendentalists in the 1800s were conscious of the social issues of the day. Today, one must also be conscious of these, although it is easier because of the different types of media available. If the people take no action or do not vote, they have no way to keep from being infringed upon.
The transcendentalists also believed that one should live simply, with few materialistic possessions. To explain this point, I must illustrate that the level of materialistic possessions has changed over the years. When cave men roamed the earth, or at least their caves, an elaborate materialistic possession might have been a wooded club studded with rocks, or maybe an especially beautiful loincloth. In the 1800s, a big house or and lots of land would have been high in value. Thoreau had a small house, 3 chairs, a desk, 2 suits, and a few books. He was able to sustain himself by growing his own food in the surrounding area. Today, the level of complexity of material possessions has risen. While all Thoreau had to do to provide enough food for himself was to go outside and plant a few seeds, today, in cities, a person would have to work at a job to earn enough money for food. I am not saying that they would have a full time job all year, but just work enough to provide for themselves. Many people today work not just to earn money to eat, but also to pay utility bills and rent. I think that it is reasonable to pay for heating bills because it is not acceptable to start a fire in an apartment, although people who have small house would just need a fireplace, after all, Thoreau didn't even own the land he lived on. The transcendentalists also did not foresee such a great population. In their time period, there were few enough people, so if someone wanted to, they could go out and live in the wilderness, while, today, if someone wanted to go out and live in the wilderness, it would be impossible because of the sheer number of people and the laws which are in place to protect the wilderness.
As I examined the multiple points of transcendentalism, I find it debatable whether Thoreau actually practiced all of them. He practiced some of them for only a limited time. He did start out with money, and he was not totally self-reliant in the fact that he did not make the axe he used, didn't carve the handle or mine and forge the axe head. He also did not make the glass he used in his window. Today, it would be possible for someone to practice some of the aspects of transcendentalism, while putting other aspects into practice would be nearly impossible.