They should turn Mecca into a 5-star Disney Worldesque resort for tourists. They could have parades and people dressed up as characters from the Koran. It would sustain their economy into the next century, at least. Medina could be their Epcot Center.
"Ah, you miserable creatures! You who think that you are so great! You who judge humanity to be so small! You who wish to reform everything! Why don't you reform yourselves? That task would be sufficient enough."
-Frederick Bastiat
-Frederick Bastiat