Unity had a "Live Training" demo called Events: Creating a Simple Messaging System.  This is often pointed to as an example of using the UnityEvent class that was introduced in Unity 4.6.

While this was a fun and educational video, it uses UnityEvents in a very odd way, wrapping them in a string-based notification system and hooking everything up in code. Honestly, you could have done exactly the same thing using standard C# events, and it wouldn't have made any difference. (Indeed, prior to UnityEvent, many Unity developers — myself included — did exactly that.)

So I decided to make my own video, accomplishing the same demo but using UnityEvent the way nature intended. The result is a lot less code, easier to maintain, and harder to screw up.

The demo project may be downloaded here.  Note that it uses the explosion effect from the KTK Effect Sample Set (free at the Unity Asset Store).