Forum:Where'd you find your Mega Cannon?

Hi Borderlands community. I know that there is no specific spot to find 99% of the weapons in Borderlands, but I do know that some people have certain "lucky" spots for finding weapons. The Mega Cannon is the LAST gun I need to find. I have found every other Eridian/Legendary/Pearlescent and it's bothering me a great deal. So I ask - Where did you find yours?

PS: I don't need a copy of one. I just want to be able to say that I have found Every Legendary/Unique gun in Borderlands.