Howard Feldman at ONLamp.com - Advanced JavaScript III:

"In this final article of the series, we proceed with another handful of useful JavaScript case studies that focus on manipulating and rewriting the HTML page on-the-fly using Document Object Model (DOM).

[...] Dynamic Tables: It is often desirable in a user interface to have the user input data into a variable number of rows. For example, when filling out an order form, the customer will fill in one item per row. With JavaScript, we no longer have to worry if we put enough space for the order though—let the user add and delete rows as needed!"