I know this one's old, but I hadn't seen it in awhile...
“God”, a Scientist exclaims, “we don't need you anymore. We've finally figured out how to create life out of nothing: We can now do what you did in the beginning."
God’s eyebrows raise: "Oh, is that so? Tell me... "
"Well, " says the scientist, "simply put, we can start life from dirt, mold it, manipulate it’s chemical components, and make man”
"Well, that's interesting. Show me."
So the scientist bends down to pick up some dirt…
“Oh no, no, no... " interrupts God. Get your own dirt!