A generally positive exclamation, along the lines of "way to go" or the slightly older "excellent!." Originally from the Jonathan Coulton song Flickr and popularized by the podcast BadPhilosophy. Also can be used as an agreement.
A word coined by Charles Manson to describe to describe himself and his followers as "slipping out of society". Similar to hippies in that both groups partake in lots of acid and sex, but preferring theft and murder to peace.
No man, Mansons group were slippies not hippies. Hippies don't go around murdering people.