Empresa engajada
Make a form, submit it, ajax submit it, add place holder, stop submit from bubbling, make a block grid which on hover each block is an opaque thumbnail and the rest translucent using only CSS, oh and make the block your hovering over appear in a large area overhead.
Sigiloso
So I mentioned using frameworks for the block grid. Nope, make it for us right now, don't look up exactly how to do inline-block display, doesn't every web developer memorize how CSS properties work? Do you want me to write web applications or another CSS layout framework. Seriously, if you decline developers over CSS/wanting to use a CSS framework, your failing at screening. (Oh well guess I'll just take my talents to Microsoft) The rest of the JavaScript questions were fairly pedestrian. Use jquery to catch the click and immediate, serialize form data, use the form URL in the ajax call etc.