We recently saw the No Impact Man movie on Netflix which was interesting as I have read the book as well as participated in the No Impact week project.
The movie is a good watch if you want to get an insight to what the No Impact Man project was all about for Colin Beavan and his family. However, if you are more interested in the project I recommend you read the book, the movie is fun if you already have read the book but if you have not I think it can leave you wondering a bit over his choices and his reasoning. The movie is a good addition to the book though and it was fun to see some of the things "live" that I had read about in the book.
If you want to try to do a lighter version of the No Impact Project you can participate through the No Impact Project's webpage.