Vault Boy! *insert 40's jingle here*! Don't know who Vault Boy is because you didn't play Fallout?
No problem!

"In the Fallout games, Vault Boy is used to provide an iconic representation of almost all stats (perks, traits, skills etc.) and items in later games available to the player character, also in achievements and trophies for Fallout 3 and Fallout: New Vegas as well as the mascot of the series. In appearance, he is a young male cartoon character with wavy blond hair wearing a vault jumpsuit. He most commonly expresses a wide grin, but has been shown to make other facial expressions as well."-Fallout Wiki
Hope you enjoyed!
PS. You are allowed to alter this skin if you wish. To post it to the internet, you must give credits to me.

Reference pics:http://www.tumblr.com/tagged/vault%20tec%20boy