A scale in which a WTF is measured, usuall from 1 (worst) to 10 (best). Mostly used by 1337 uber geeks who play unreal tournament, lolcats and other extreme creatures
Person: " OMG! that scored a 7.6 on the wtfometer!"
Person: "You're so gay you score a 2.3 on the wtfometer! k thx bye!"
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.