Variable Cell Range

Is there any way to define a 'variable' cell range?

For example, I have created a drop-down box using Data Validation and defined a cell range for options to appear in the drop-down box. The problem is I want to be able to add items onto the end of the cell range and have them appear as new options in the drop-down box WITHOUT having to redefine the cell range in the Data Validation dialog.

So far the best i've got is to simply define the cell range as the ENTIRE column where the list of options is located. When i add new items to the bottom of my list they DO appear in the drop-down box, however a lot of unwanted blanks appear aswell.

Found a solution: http://www.contextures.com/xlNames01.html#Dynamic