If you could bid cheaply and get a ton of traffic to Facebook urls with no competition on them , What kind of LP would you build and for what offer would you promote to Facebook url targets ?
Thanks
I've tried targeting FB URLs with PPV and built out LPs for a wide range of things, including games, mobile/iq, toolbar downloads (Pagerage), etc. And just couldn't get things to work. I got the impression that the traffic was too broadly targeted to really convert. I tried creating LPs with several offers in a sort of "today's most popular posts/apps" style imitating FB, but that didn't work either. Fail. I think the best bet though is probably games...
never worked for me, too! 
Lead Impact and TrafficVance are both cracking down on people targeting Facebook related domains and keywords. You can still target deeper stuff and work around the restrictions, but the volume is definitely lower than it used to be. My LI rep told me that the sheer volume of facebook.com was putting too much strain on their system and that's why they blocked it. Not sure why TV did but it's probably something similar or a legal issue.
I'm not saying it's impossible, it's just tough to make it work.