Facebook is trialling coupon-based ads, providing brands with a new way of targeting their fans.

The coupons can be posted on a brand’s Facebook page wall, and then also appear as clickable ads on a user’s homepage.

If a user clicks on a coupon then Facebook posts the action to their wall and sends an email that confirms details of the offer, encouraging the user to share the deal with Facebook friends.

Facebook said, “We think the test is complementary to the other products we offer businesses and hope to learn more about how it might work for both merchants and customers.”

News was also leaked yesterday about Facebook’s plans for a mobile advertising product that it could launch by the end of March 2012.

The move is an attempt to take some of the market share currently held by coupon giants such as Groupon and LivingSocial, but Facebook has tried and failed in this market already with its ‘Deals’ offering, which lasted only four months before being dropped in August this year. 

Discount deals are still very popular with consumers, with 56% of people saying they would buy from an unfamiliar brand if offered the right deal at the right time. But Groupon’s recent troubles following its IPO, and a looming investigation by the Office of Fair Trading show it is difficult to get right.

Facebook will also face tough competition from Foursquare, which reached 15m users this month, and Google, which confirmed last week at LeWeb that it is trialling new location based services.

The coupons ads are slightly different to Foursquare’s deals as they don’t appear to be based around a user’s location, but Facebook may look to integrate the coupons with its own location service following the hiring of Gowalla’s co-founders this month.

The company seems to be working hard on creating, streamlining and strengthening its revenue streams ahead of a rumoured IPO in the middle of 2012.

And if the test is a success, expect to see the coupons showing up in your news ticker in the New Year.