http://www.gomage.com/extensions/advertising-marketing/gomage-feed-pro.html/

Fantastic extension. GoMage Feed Pro - Feed Manager for Magento allows you to provide information about products from your online store to search engines like Google Product Search (Google Base), Yahoo! Store, eBay, Amazon.com, ChannelAdvisor and other sites that collect and show information about your products.
Features of GoMage Feed Pro:

Unlimited number of feeds on your store
Ability to send your product data to all Search Engine Services you utilize
Ability to send product data from any of your Magento stores directly
Ability to send different data and prices to each of these places
Providing a permanent URL for Search Engine Services
Ability to send your product data files through FTP
Ability to automatically send your product data files using business rules
Set the Auto-generate and Auot-Upload times for Feed files
Ability to set Passive mode Enable or Disable
Easy Fields Mapping with ability to use Output Type filter for every column
Import And Export Fields Mapping into the Server
Advanced Product Attributes Filter Configuration
Ability to filter products by Product Type (new)
Upload Out of Stock Products in the Feed file (Option)
Upload Disabled Products in the Feed file (Option)
Upload Categories and Sub-Categories
Upload Images
Ability to resize uploaded images (new)
Ability to use Characters Limit for names and descriptions (new)
Ability to remove line break symbols from a data feed
Ability to use header for Amazon (or another Search Engine Services) (new)
Supported formats: csv, txt, xml
Ability to use File Creation Settings for slow Servers
Ability to use Dynamic Attribute that allows you to set your own conditions for Categories, Prices and etc
Import And Export Dynamic Attributes
Easy installation requires you simply upload files without the need to change code or templates.

http://www.gomage.com/extensions/advertising-marketing/gomage-feed-pro.html/

http://www.gomage.com/extensions/advertising-marketing/promo.html/

GoMage Ads & Promo extension is a simple, flexible, yet powerful solution for advertising and promoting your products, prices and campaigns on your Magento store. The extension allows you to select from the following category or product pages to place in your promo images and windows.
Features of GoMage Ads & Promo:

Allows you to advertise and promote your products, discounts, news and special events
Allows you to manage the promotional period start and end dates
Allows you to promote only on the product page(s) (new)
Allows you to count the clicks. Now you will know what is intresting for your customers. (new)
Allows you to add and display social network bookmarks
Easy to add and display corner and sides images
Easy to add and display promo windows
Allows you to use effects
Allows you to specify how many times your customer will see the same promo window (new)
Set Indent for Promo Images and Windows in pixels or percents (new)
Involves customers in campaigns
Display videos from YouTube and others services on product pages
Allows you to include multiple ad units per page
Select which position (left/right, top/bottom) of the page to display ad item
Display Magento blocks as contact form, newsletter subscription, cart and many others in the promo window
Extension is easy to customize with separated layout form and CSS
Easy installation of the extension allows you to just upload files without changing codes or templates.

http://www.gomage.com/extensions/advertising-marketing/promo.html/

Let your customer enjoy a comprehensive social shopping experience.This extension provides many functions that can be divided into 5 modules:

Social Identity: Allows Facebook users to register and login without any registration hassles.

Social Discounts: Offers many kind of discounts, including a user friendly referral system with rewards.

Social Recommendation: Segment your customers and catalogue with tailored recommendations using many variables such as: Age, Gender, civil status among others.

Social Engagement: Allow your users to Like your products, and create public/private discussions around your catalogue.

Social Analytics: Get to know your social customer through a specific set of reports.

Enjoy also our Facebook Theme to create a new and successful point of sale on the biggest social network.