Are you talking about a thumbnail viewer? A popup window? A popup that shows more details? Please be more specific.
Also check out this: http://jqueryui.com/demos/dialog/#modal-form
First of all, I don't know what the thumbnail viewer is called, the one when you click the quicklook button then a window or lightbox pops out. Sorry for not being specific.
Do you have a sample code for that modal? The one with a quicklook button just like the product page of gap website?
And by the way, thanks for your response :)