'Compare Cart' for website onsalenow.ie

[login to view URL] does not 'sell' directly but advertises products on the website for other retailers however compare and bookmark features at a product level are lacking. Effectively we wish to allow user to add all products he is interested in to a Personal Compare Cart. Essentially it is similar in function to Shopping Cart without the click through to payment pages - but a click through to a retailer product view page. Effectively it allows the customer to 'bookmark' all products he is interested in and 'compare' them side by side and then save his selection. The 'Comparison' will be quite basic as it is dependent on the attributes common to all/most products - mainly, retailer name, department, category, product name, price, brand, sale end date, offer....very short description. Detailed List or Requirements: - add a +Compare button to the product description page/template - add a similar feature to the product grid - (for the above the Cart should be dynamically updated - solution should have good usability) - add a compare cart page with products listed side by side with principal attributes available and image (the department/category listing to the right of all pages can be removed for space purposes on this page) and the look of this page needs to be defined in terms of screen space. - caching of 'compare cart' within user session (i.e. guest user) - ability to 'save' the 'compare cart' using email address as login and a chosen password (actual user) - cookie may remember user if they re-access (i.e. remember user when they access the site again) - ability to remove items from the 'compare cart' - Compare Cart button somewhere on homepage (need to decide optimum but probably top right hand corner) (this acts as login/register prompt if new user or cached items if user has already added products) (should show number of products added dynamically) - backend admin to manage 'compare cart' users (capture email address, products saved to compare cart) - backend admin allow edit/delete of 'compare cart' users (user account management) - basic admin statistics on 'most popular products' added to 'compare cart', 'most popular retailer', 'most popular brand' - statistics on 'last signed in' date - counter on number of sign-ins.