This functionality currently exists within BeerSmith. On the tool ribbon, there is an icon labeled 'copy to log'. When you highlight a recipe and click on this icon, the program will transfer a copy of the recipe to a new folder called 'brew log'. In this folder, you can make any changes, assign a brew date, enter brew day data, and basically do whatever you want without affecting the primary recipe in your 'my recipes' folder. You can have multiple copies within the 'brew log' folder of the same recipe to record different brew sessions and each recipe will be a self-contained archive of that brew session. Changes to the primary recipe in your 'my recipes' folder will not affect any other copy of the recipe.