Jack Shepherd from Lost. Whenever he squints and you can see his teeth, we call it Jackface. He does it ALL the time, mostly when he's frustrated, but also when he's amused, bemused, hungry, sad, confused...
Also, everybody's always looking for Jack.. There's a song by Colin Hay called "Looking for Jack" which applies to Dr. Shepherd very, very well. Here are the lyrics and possible Lost connections (I am aware that the song is older than Lost, this is just for fun)
Looking for Jack by Colin Hay
Everybody's always looking for Jack In the fire and in the water (fire and water is a Lost episode) Everybody's always looking for Jack In the streets and on the corners (Jack WALKS on streets)
I always wanted to be like Jack He's as cool as they come (Not as cool as Sawyer) Yeah I always wanted to be like Jack Still for me, he's the one
Someday...Someday... (Someday Kate will get something you ask her for without having to say "Kate!" to make her do it) Someday...Someday...
Hear the wind blow through the long grass (Smokey?) I hear laughter in the night (The Others) No revelations as the years pass (Hardly any reveals until now) They disappear from sight (Others again)
As I grow older I grow younger (Richard Alpert) Every day is like a dream (Sometimes they dream) I wouldn't go back for a moment (In time?) Except for maybe seventeen (Des could do it)
Someday...Someday... Someday...Someday...
Everybody's always looking for Jack In the fire and in the water (Again, Lost episode title) Everybody's always looking for Jack In the streets and on the corners
Even Jack is always looking for Jack (Find yourself, Jack) He's always in another room (He's never around for women) And when I spoke to the woman there (Sarah? Kate? Juliet?) She said he left this afternoon (Christian left too)
Many applauds for drawing Jackface is all its Jackfacey glory. <3