A disclaimer should be made, because I am far from an expert on fungi (not even close). It's just that botany and such is one of the topics I really love - so whether plants, fungi, lichen etc., it's a topic I am very interested in. This is just a collection of books I compiled after some research on the topic. I own some of these books, but not all. Majority of the aforementioned books touches upon fungi biology, and fungi in general, how they work, what they are, what they do etc.
For those who are interested in fungi, Paul Stamets' book "Mycellium Running" is very interesting, as it covers some of this. On a similar topic, that of sentience, and their importance in nature, there's two other books:
Plants As Persons: A Philosophical Botany (Suny Series on Religion and the Environment): http://www.amazon.com/dp/1438434286/
What a Plant Knows: A Field Guide to the Senses: http://www.amazon.com/dp/0374288739/
For example, Stamets demonstrates in the book "Mycelium Running" in an experiment, how one type of fungi basically is able to use diesel oil as a nutritional source, and consumes the oil as food being unharmed by it. If I water plants in the garden with diesel oil, I am pretty sure the outcome won't be a happy one!
Then there's fungi which is capable of absorbing tremendous amount of radiation, something Stamets suggests could be very useful today in Fukushima.
Fungi and slime molds are really something else as a whole, what they are capable of and what they do is really fascinating. For example, scientists have put slime molds (myxomycetes) in charge of controlling robots. In one experiment the robot walked around, and avoided bright areas, because the slime mold used in the experiment is very light shy. In another experiment, the robot drives around on a table, and avoids driving off the table itself, knowing where the table edge is.
I believe an increased awareness of how nature works, who the key players are - plants, animals or other - is important, especially when we consider how much we can impact our surroundings, both negatively and positively. It also opens up our eyes to a world that is much more alive than we may think.