We are at the end of this book. You have probably read everything and also tested some pieces of code with your own hardware, and I'm sure you are now able to imagine your future and advanced projects with Arduino.
I wanted to thank you for being so focused and interested. I know you are now almost in the same boat as myself, you want to learn more, test more, and check and use new technologies in order to achieve your craziest project. I'd like to say one last thing: do it, and do it now!
In most cases, people are afraid of the huge amount of work that they can imagine in the first steps just before they start. But you have to trust me, don't think too much about details or about optimization. Try to make something simple, something that works. Then you'll have ways to optimize and improve it.
One last piece of advice for you: don't think too much, and make a lot. I have seen too many unfinished projects by people having wanted to think, think, think instead of just starting and...