REFACTORING, by Martin FOWLER

I really enjoyed the pragmatic approach to refactoring: run the tests, change the code in a little step, compile and run the tests, and so on.
The part on test-driven development is very clear and the article on the fact that the design is the code are just great.
This book is a must read!
What I put into practice:
+ I program in many little reversible steps;
+ I refactor ;o)

I RECOMMEND THIS BOOK.