First, is controlling Beam or frame sizes with the click of a button.
Here we have a I-beam frame
In iLogic you can write code that will manipulate the beams to allow you to select different sizes as shown below:
and then once you select one it will automatically update your assembly.
This is a very basic use for iLogic...one of the things that i am working on for this assembly is coding to be able to define which wall a ladder assembly will be placed and then having supporting beam members that are able to move around in the assembly depending on which wall is selected for the ladder.
So, as stated before...there are so many possiblities when it comes to using Inventor iLogic in your design process.