10 Days Without by Daniel Ryan Day is an interesting concept of putting a person's faith into action. The thought is that when you do something different, people will notice, and the author has some really great ideas to do just that.
Mr. Day gives encouragement and a game plan how to "go 10 days without..." and a reason to do it, such as raising awareness and/or money for a particular cause. Also, he prepares us that not only will we be doing something that can affect others, but we should be prepared to be changed in the process.
One word of caution: Don't read this book unless you are willing to put what you have learned into practice.