Funny Story 

1970s/80s: You are about to lie or make an excuse.

mid90s onwards: You are in bit of a soup and you have a semi-valid excuse. So you just say "funny story" and its understood that you are not going to hold your end of the bargain.

Friend1: Did I see you driving my car yesterday ?
Friend2: Funny story... I was looking for _my_ car keys and ...

Manager: How are we placed on the back order from Big Company ?
You: Funny Story.

Funny Story by alwarming October 3, 2011

Funny Story Bro. 

The way you begin your story when you are about to lie to your friend or make an excuse.

Example1:

Christian: So Philip told me that he saw you watch a movie with my sister last Friday night.

DJ: Haha, Funny Story Bro....

Example2:

Jordan: So I heard you slept over my girlfriend's house last Friday night.

DJ: Haha, Funny Story Bro...

Funny Story Bro. by DJ Imperial March 2, 2011

Its a funny story 

Something you say when you know your screwed, and your thinking of a way around it.

Jim - "Dude, why are you driving my car?"

Dave - "Its a funny story really-"

Jim - "Shut the fuck up and get out of my car."

Dave "Ok...."

Its a funny story by ReallyQuick June 14, 2010