Shaggy Doo 

A boy with long hair, possibly homosexual, who likes to eat, act extremely weird, Facebook chats frequently, and makes rude comments to his "friends". Also doesn't refer to his "friends" by insensitive nicknames. Usually named: Jack.

Andrea: "Will you ever say my actual name?"
Jack: "Your name is BLAH BLAH BLAH!"
Andrea: "No, my REAL name....(say my name, say my nameee)"
Jack: "What's up Stank Tank?!"
Andrea: "Whatever, Shaggy Doo."

Shaggy Doo by dennythedino October 17, 2010

Shiggy diggy doo 

Originally starting as the acronym ISHYGDDT (I sure hope you guys don't do this) on 4chan, the acronym was later extended to 'Shiggy Diggy Doo'. When the term first came into use, many newfags thought it was also an acronym, so it was often said as 'I SHIGGY DIGGY', which was implied as an acronym for 'I sure hope I go get young dogs in good gay yelps', which was a reference to the massive amount of furry pornography that flooded the site during that time. Even today, the phrase is in use on many mainstream internet sites such as 4chan, reddit, tumblr, digg, funnyjunk, and facepunch.

Guy 1: Hey dude, I just bought myself a pack of ciggs. Want one?

Guy 2:
>Any year
>Not smoking weed instead of pleb-tier cigarettes
>Shiggy diggy doo

Shiggy diggy doo by Shiggy diggy doo November 25, 2012