© Drew Morris

The online coupon site Groupon has made big news lately, as it's membership has grown to 60 million worldwide, with half of those in North America.

They have a simple business model, where they post one deal a day , such as half off at a local cafe or a buy-one-get-one-free clothing deal, and visitors have 24 hours to sign up for the deal. Groupon's success has spawned numerous copycat sites, and while the formula they use is pretty much the same, the mix of bargains you will find from site to site can vary a lot. Groupon will sometimes offer deals at national chains, and offers the best variety of deals. Many of the deals are good for between 6 months and 1 year, and each deal needs a buy-in from a certain number of people to take effect. Because Groupon is so large, most deals do meet their buy-ins, and Groupon now even has apps for iPhone, Android and Blackberry.

© davidwilson1949

HauteLook is one of a new generation of online fashion deals sites, and it's success has attracted the attention of one of the most prestigious US department store chains, Nordstrom. HauteLook is set to be acquired by Nordstrom for $180 million in stock, but the price could rise to $270 million depending on the future performance of HauteLook. The president of Nordstrom, Blake Nordstrom, said that the company is actively seeking ways to use new technology to give it's customers more options.

HauteLook was established only four years ago, one of several "flash sale sites" that specialise in offering limited time fashion deals. This is definitely not the first deal to get done in the space, with GSI Commerce buying Rue La La for $350 million in 2009 and Amazon acquiring BuyVIP last year for $100m.

© Franco Bouly

While you may already shop for online fashion deals, you will be able to do this soon via Facebook. The social networking giant is planning to offer a free service that will allow retailers to broadcast deals to all Facebook users in a specific area. This service, called Facebook Deals will work with Facebook Places, which allows users to "check in" to locations with their smartphones. In this case, Facebook Deals will allow users to check in at their stores and receive special deals.

Major fashion retailers hope that Facebook Deals will get people off the streets and into their stores , as well as that people will share the location with friends. While the full impact of this new type of 'social commerce' is yet unknown, it is likely to be significant.