JavaScript is great for traditional client-side validation and dynamic behaviors, it's also great for less conventional uses such as game programming, on the web.
Flash, of course has become popular for writing web games too, but some of the cooler aspects involve supporting customizations, such as the jigsaw puzzle examples below.
Cascading Style Sheets are very powerful.
By using them to implement site designs and interface you can save serious time.
When implemented externally and called in through the <LINK> tag simple changes can have wide impact.
syntax:
Include in section
Include within specific HTML tags
(when a class is defined elsewhere)
A client was using customer phone numbers to look up account info.
They wanted a form which would automatically move the focus to the next control
when the customer entered the expected number of digits into each field, ending
on the submit button.
This code does that.