More than a simple Diary or a PIM. It is instead a total personal information manager. It can be as simple or as extensive as you want it to be and it can be fully customized to meet all your current and future needs.
Weight-By-Date Pro is the most complete diet software available for your PC. It's a carb counter, calorie counter, and food diary all rolled into one. It also logs your weight, exercises, body measurements, daily notes, and motivates like no other.