Doing something purely for fun vs doing something with the expectation of profit is the big difference - it is essentially the difference between work and play.
…you're allowed to do with this page anything you wouldn't mind me doing with your cat. So yes, you can photoshop it for comedy effect, you can copy bits of it for illustrative purposes and so on, but you can't steal it and pass it off as your own.
On the other hand, I took a more unique approach: I pointed out that fruit was an ingredient that commonly shows up in jellos. So I nailed my jello to the wall through a ring of apple and relied on that to hold it up.
Sticks to a wooden "wall" (when slowly raised) -- what if it's painted? I guess I need to get some jello.
There were other very nice examples as well (cannot find the post right now but will look further tonight)
They had a studio down on Vermont or something in LA and had to change the mural on the building to update the name.