FBG aka Freebandz Gang, a record label founded by hip-hop artist "Future".

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

Fat Bottomed Girl. Speaks for itself. From the song "Fat Bottomed Girls" by Queen. Note that rather than applying the term in a derogatory sense, as one might think at first, the song actually praises fbgs.

a.k.a. fat bottomed girl, a women with wide, voluptuous, curvy, plump hips and ass. The kind of gal who screams squeeze my ass. A women, who, in springtime always makes the two letter word answer to the question "what's up dude?" start with the letter m and end in the e.

Fuck Bitches, Get Successful.

Fizzy Bum Gravy - A result of eating mystery dishes and strange foreign foodstuffs, or from inadvertently drinking the local water on foreign land. The next day, said concoction plays havoc with your intestines to the point that any loud noises or sudden movements will make you shit yourself. The resultant explosion from your arse sounds like the last of a washing up liquid bottle, emptying the entire contents of your bowel in 3 seconds. The by-product of this experience is known as FBG.