Let's focus on the shopping side. Who has not heard about eBay or Amazon?
Few weeks ago I was reading this article on "The New York Times": http://www.nytimes.com/2012/03/01/fashion/virtual-closet-web-sites-like-pinterest-and-stylitics-revise-online-fashion-shopping.html
It talks about a new social network called thefancy.com. This is a social photo sharing website where you can connect to different users sharing tastes and the "things" you find interesting. It is definitiey a new style of social network so I totally encourage you to check out the web: http://www.thefancy.com/
Here is the icon so you can get used to it! :)