Abdomen crunches worked for me! But I didn't have too much fat so it wasn't that much of a problem. If you have a rotund stomach then you will be better of trying to lose weight through cardio and physical activity. Some of the best exercises for losing stomach fat are as follows,
• Hoola hooping
• Belly dancing
• Tai Chi
• Kickboxing
• Swimming
• Running
• Cycling
A combination of all these exercises is a good option as well. You can go in for the jogging and swimming combo or the kickboxing and cycling combo depending on what you like.