How to stop Numbers from beeping at me when I use the arrow keys?
The keyboard shortcut for going to the last cell of a row: ⌘+Right Arrow

The keyboard shortcut for going to the first cell of a row: ⌘+Left Arrow

The keyboard shortcut for going to the last cell of a column: ⌘+Down Arrow

The keyboard shortcut for going to the first cell of a column: ⌘+Up Arrow

This will save holding the arrow key down repeat extending beyond the table bounds resulting in the annoying beeping/screen flash error.