A common picture on 4chan of a young man, giving the thumbs up sign and grinning eagerly in front of a yellow sports car, thus giving him the name 'happy hipster', for his fad of sports cars and his friendly grin. Many people photoshop the picture of the man onto related pictures of a 4chan posters topic.
It is mainly found on /b/, though every board has taken this fad.
"Will someone post a picture of some hot Russian chicks puking in each others mouths?"
*Insert happy hipster here*