One advantage of JavaScript is that it doesn't cost anything. If you are paying for JavaScript then you are going about things the wrong way. Not only is JavaScript itself built into the browser but there are sufficient free JavaScripts that people make available for you to download that cover just about every task you can imagine meaning that there are next to no situations where you should ever need to pay for someone to write JavaScript for you.

Free JavaScript Download

JavaScript can easily add new content to an existing web page.

In the tenth Document Object Model tutorial we looked at how to create new elements for our web page but we didn't actually add them to the page. In this eleventh tutorial we look at what needs to be added to that code if we want to add the element into the web page as additional content.

appendChild

JavaScript can put a fireworks display on your page - no images required. Share any celebrations with visitors to your web site with a fireworks display right on your web page.

Fireworks

The weather on the web is under your control using JavaScript. Where I live it is Summer. For those of you in the northern hemisphere it is Winter and for some of you at least that means snow. On the web though no one needs to miss out on seeing snow without all of the inconvenience that it has out in the real world.
Regardless of where you or your visitors live the Falling Snow script means that you can have a light snow fall on your web page for all to share at any time of the year.