Example of the Yahoo store with new direction of design and many advanced features installed.
From the list of recommended to review addons: Dynamic Top Header, Scroller in Top Menu, Central banner Rotator, Central Apple-like scroller, Related Items on Product page, Product review with CAPTCHA,

List of Addons

• Cascading Menus (RTML or DHTML)
• Top/Bottom Editable Menu
• Home Page Spot with Content Rotator
• Home Page Table with "Bestsellers"
• Table with "Related Items"
• Order-Ready Listing Page
• Home Page Dynamic Content Rotator
• Pagination of Listing Pages
• Multi-Line Breadcrumbs
• Editable Text/Image Page Spots
• Automated "HOT LINKS"
• "Tell a Friend" Form
• Hierarchical Site Map
• Favicon Design and Setup
• Custom .CSV Data Export
• SEO: Google Rich Snippets (Microdata)
• SEO: Canonical Tags
• SEO-Related Page Settings
• Multi-Type Item Options
• "Currently Viewed Items" Table
• Image Enlarging (AJAX Lightbox)
• Multiple Insets
• Custom "Availability" Text Field
• Quantity Box for "Order" Button
• Item Discount Calculation
• Item Total Price by Selected Options
• Item Total Price by Quantity Input
• Minimum Item Quantity
• Enhanced Accessories at the Product Page
• Floating Shopping Cart Customization or Custom Development
• jQuery Pagination of Listing Pages
• Style Customization of Checkout Pages
• The Product Rating & Comments System
• Find Uncharged Orders