I just came across Perfect Audience, a company that offers retargeted ads on Facebook. So basically what they do is after you insert a few lines of code into your website they start placing cookies on the computers of anyone who visits your site, then when this people log in to their Facebook they will be served your add.
The value proposition is definitely tempting. Why on earth would someone who has already visited your website (therefore have your cookie and are now being served your add) click on one of your ads if they hated your product right? Someone who click on these kind of ads should be that more likely to convert, at least in theory.
I’ll give it a try and let you guys know how it works out.