The big green JR is in both Murky Hollow and the Catacombs, definitely...
I have a screen shot of the one in the Catacombs too, but it's not currently hosted anywhere...
EDIT: OK. I published some more shots on my guild blog and here's one of the Jolly Green Giant Jolly Roger in the Catacombs. The quality isn't as good because I had my graphics set to medium and I was running for my life...And the HUD was off so, sorry about that:
