This Thing of Ours translated from the Italian phrase, "La Cosa Nostra", also meaning "Mafia". This thing of ours refers to the Italians who created the modern Mafia, it was "their thing", "their own thing" that they created.

Our Chart was used in the television series, The L Word, as a way to track whom has had sexual relations with whom.
Although "Our Chart" was inclusive to all, it was generally most often used by lesbians, and bisexuals.

A social networking site. The series DID launch a real world website. www.ourchart.com which no longer exists.

a very amazing band from melbourne, doing what they can to be the best they can.

"A friend of ours" is a made guy in the mafia. This term is used when a mobster is introducing another mobster to his mobsterfriends.
When a mobster is introducing a friend who is NOT a mobster to his mob friends, he will say that the person is "a friend of mine."

An alternative way of saying "your mom", but with your friends. Also a way of saying communism of "your mom" as there is the word "our".

common way of describing girlfriend

A phrase used by you and your friends to warn each other of a creeper approaching.