I have found industrial design to be separated from typical mechanical engineering by two major factors: moving quickly through concepts, and user centered design.
In my current aerospace work, I find this style of concept development particularly useful for tooling design, where human factors dominate the equation. Ditching the computer screen and designing tools hand in hand with the technicians using them is a powerful recipe for making things people actually look forward to using.
For a look at some of the user centered design projects I can actually show you, check out Optik and DuoDesk
Here’s a sampling of my sketching work: