Removing and Adding Options Dynamically

Using DHTML is beautiful because you can play with the DOM as you please. However JavaScript is not that consistent. Of all sources I find the one by W3C: W3 Schools the most comprehensive and technically correct.

If you are looking to add or remove options from a select box dynamically, using add and remove methods on select element is the most reliable way. For gory details have a look here:

Select Object Reference

Large Numbers in JavaScript

Recently faced probelms with large numbers in JavaScript. These two resources were extrelely useful:
Hazards of large numbers in JavaScript
Big Integers in JavaScript

Hope it helps you too :).