2 different ones have worked really well for me.
The first one was the Protein Power plan. Very similar to Adkins, only less "structured". The real component is to limit carbs below about 30 grams per day and be sure to eat "enough" protein... which for me was around 50-60 grams per day. Around 20 grams per meal 3 x per day or just 15 at breakfast with a 4-8 gram protein snack at some point during the day (think, a couple of thin slices of apple with peanut butter slathered on it or a handful of almonds).
It worked beautifully, but I felt really restricted by not being able to eat sandwiches or any bread, pretty much. I did it for 6 months and lost most of my post pregnancy weight after # 2 was born.
The most recent thing I have done is called The Alternate Day diet. Again, very simply and not much "counting" or "measuring" involved. Anything too labor intensive just doesn't work for me. I find that I often get going without eating anything and it is 11:00 or 1 pm before I notice that I missed breakfast (and lunch!)... So, when I came across this plan, I tried it. Did it for almost a year straight and I like it even better than the Protein Power plan. Some people have a hard time with it, but it worked well for me, since I naturally skip meals anyway. Basically, you restrict your calories every OTHER day. Typically I would eat 450 calories or less (half and half in my morning coffee, half an apple at some point, and low cal soup for "dinner") on my "down" days. And then the next day ("up" day) eat whatever in whatever quantity I wanted. Then continue alternating up and down days. I lost about 25 lbs over the first 8 months I did it. And I stopped having heartburn, swollen fingers when I woke up in the morning, and general aches and pains. It was designed to reduce inflammation in the body--- the weight loss is just a plus. I also found that the weight I lost was around my middle (the hardest for me to lose, and the most important fat to lose; the abdominal weight is the most dangerous b/c it is stored in your internal organs). I also discovered that I was chronically sleep deprived and had been using food/snacks as a way to get through my day when I should have just been sleeping more. I also found, that once I got into a routine with it (about 2 weeks in) that it got a LOT easier, and that I ate less "junk" when I could eat whatever I wanted. Mainly, I couldn't eat as much at one time, so I was much more judicious in my food choices, and I had NO GUILT if I wanted a piece of chocolate or popcorn at the movies. I "supplemented" with lots of Vitamin Water 10 or Vitamin Water Zero. Or just plain lemon flavored water. Usually when we are really thirsty, we think we are hungry so we eat. If we drink water first, we find it was actually thirst, not true hunger.
Some people I have mentioned this plan to have not been able to tolerate the restricting days, but others do well with it, like I did. I quit over Xmas, and am getting ready to go back on it again.