facelink chain
When you click on your friend's Facebook page, click on one of his/her friend's page, clicking on one of that person's page, and so on and so on, often done because you see a person that is good-looking, hot, etc.
Guy: Dude, I saw some chick on Rob's Facebook and clicked on it to see the picture bigger, ended up seeing a hoteer chick on this girl's friends list, and ended up seeing another hot chick on that girl's page.
Dude: You just experienced a facelink chain.
Dude: You just experienced a facelink chain.