IE7 loads and parses all style sheets into a form that Explorer can understand. You can then use most CSS2/CSS3 selectors without having to resort to CSS hacks. The lightweight script is a single-line inclusion in your HTML/XML document. No alteration of your original markup is necessary. Neither do you have to alter your CSS.
Perhaps I am the only one who thinks it’s incredibely stupid confusing to name a javascript project with the same name as a popular web browser. Oh well. It’s confusingly named, but it works absolute wonders.
Here is a list of some of the things you can “add” to Internet Explorer 5/6/7 :
- supports the following CSS selectors:
- namespace|selector
- parent > child
- adjacent + sibling
- adjacent ~ sibling
- [attr], [attr=”value”], [attr~=”value”] etc
- .multiple.classes (fixes bug)
- :hover, :active, :focus (for all elements)
- :first-child, :last-child, only-child, nth-child, nth-last-child
- :check, :disabled, :enabled
- :root, :empty, :contains(), :not()
- :before/:after/content:
- :lang()
- works with both HTML and XML documents
- supports imported style sheets
- preserves the cascade of the style sheet
- does not alter the document structure
- does not repeatedly query the DOM
tree using JavaScript - uses pure CSS to enforce style sheet rules
- supports the W3C box model in both standards and quirks mode
- supports fixed positioning (flicker free)
- supports overflow:visible
- supports min/max-width/height
- fixes broken (X)HTML elements (abbr, object)
- standardies forms behavior
- supports PNG alpha transparency
- lightweight script (22K)
- completely modular (add/remove fixes)
- works for Microsoft Internet Explorer 5+ (Windows only)
I know you’re as excited as I am. 
Wandering the Interwebs 