One of the best types of diets I have ever used to stay lean and have used it in the past and am currently using is the Cycle diet created by Scott Abel.
Generally speaking you are in relative calorie deficit the whole week and one day a week you have a re-feed day. The amount of carbs, fat, protein are irrelevant as long as you spike you calories. You have to be in a supercompensated state for this to be effective or you will gain fat. The purpose of the spike day is to upregulate your horomoves (thyroid, leptin, etc..) because when in a relative calorie deficit these start down regulating so the spike day jacks them back up (hence the term cycle diet). This is same concept as having cheat meals during a contest prep, so you upregulate metabolism. You have to be very strict during the week. Bio-feedback signs to look for are hunger levels (you should be hungry most of the day), have a huge appetite, and your weight returns to normal by the next spike day. These are a few signs.
You will know if you are in supercompensation mode because you will be able to handle large amounts of food without really getting that full. I usually take around 8000+ calories on my re-feed day. Now you also have to pay attention to your energy and performance levels during your workouts. If they are dropping towards the end of the workout week you may need to add in a Mid-week spike meal. Like for myself I have a Mid-week spike meal (which replace my last 2 meals of that day) on Wednesday and Saturday is my re-feed day.
Scott has a DVD of a seminar he did on it which is very informative. This is a diet where you can have you cake and eat it to
I actually used a verison of this when I leaned down and went from 215 lbs to 200 lbs in 10 weeks with a whole re-fee day every Saturday and the last 4 weeks added in the Mid-week spike and was doing no cardio.