What could be more simple than the Zoom command, right? Many people I see primarily use the center mouse wheel for zooming and rarely use other zoom options. However, there may be times when you want to zoom to a specific area, meaning you need more accuracy than you can get with the wheel. Most people are familiar with Zoom > Window, you pick two points that define the corners of a rectangle. Others know about Zoom > Center. This is where you pick the center point and then enter the new view height. This can be useful when initially setting the view in a viewport.
I wonder how many people remember Zoom > Left? This has been undocumented since R14 and it works just like Zoom > Center, except that you provide the lower left corner coordinates instead of the center. Another undocumented (since R12 I believe) Zoom option that still works today is Zoom > VMax. This will zoom out to the maximum area possible without causing a regen.
Zoom > Dynamic is still documented and available as a visible option when running the Zoom command, but I can’t tell you how long it’s been since I have seen someone actually use this.
Zoom > Object is another option I rarely see people using, but the king of “hidden” zoom options has to be the command DSVIEWER. OK, when is the last time you used this command?