For me juice fasting was very effective. It leaves you with a very energized positive feeling. Make sure you read up first. The website in the previous post has good info.
Also check out a book by Dr Stephen Bailey called
"The Fasting Diet". He is one the experts in the field. The book goes into great depth about the whole process, and has a five day plan.
Also, www.easytojuice.com for over 100 delcious juice recipes.