Modify > Timeline > Distribute to Layers
Here is the first little gem I wanted to post about. We were watching a user working on a project in Flash, and they had imported about 20 images which all got imported to the same layer on the stage. They then began to manually move each image to its own layer (a very tedious process). Of course, Flash has a “Distribute to Layers” command that does exactly this. Basically, select all of the items / objects on your stage that you want to distribute to their own layers and select Modify > Timeline > Distribute to Layers (SHIFT-COMMAND-D on Mac). This will place each item on its own layer of the timeline.
The user was really excited to learn about this and used it to distribute the images to their own layers. However, they then used the command in a way that surprised me. They had accidentally placed two items on the same layer. I do this all of the time, and usually cut the item (Edit > Cut), create a new frame, and then paste it in place (Edit > Paste in Place) on the new frame, a really tedious / annoying process. The user just used the Distribute to Layers command to automatically place the item on its own layer. Something really simple, that I had never thought of, but will save me a lot of hassle in the future.