Adding a drop-down menu in Excel can make your spreadsheets more interactive and efficient. You can use the Data Validation feature to create one. Simply select the cell where you want the menu, go to Data > Data Validation, and choose "List" from the Allow menu. Then, type in your list items or select a range with predefined values. What kind of project are you working on that requires a drop-down menu? I'd love to hear more about it!