jQuery remove special characters from string and more

Assuming by "special" you mean non-word characters, then that is pretty easy.

str = str.replace(/[_\W]+/g, "-")

replace(/[^a-z0-9\s]/gi, '') will filter the string down to just alphanumeric values and replace(/[_\s]/g, '-') will replace underscores and spaces with hyphens:

str.replace(/[^a-z0-9\s]/gi, '').replace(/[_\s]/g, '-')

Source for Regex: RegEx for Javascript to allow only alphanumeric

Here is a demo: http://jsfiddle.net/vNfrk/

str.toLowerCase().replace(/[\*\^\'\!]/g, '').split(' ').join('-')