An elf walks into a bar and asks the orc bartender, "If I show you a really good trick, will you give me a free drink?" The orc considers it, then agrees. The elf reaches into his pocket and pulls out a tiny fairy. He reaches into another pocket and pulls out a tiny piano. The fairy stretches, cracks her knuckles, and proceeds to play the blues.
After the elf finished his drink, he asked the bartender, "If I show you an even better trick, will you give me free drinks for the rest of the evening?" The bartender agrees, thinking that no trick could possibly be better than the first. The elf reaches into another pocket and pulls out a small bullfrog, who begins to sing the blues along with the fairy's music.
While the elf is enjoying his beverages, an ogre confronts him and offers him $100,000 for the bullfrog. "Sorry," the elf replies, "he's not for sale." The ogre increases the offer to $250,000 cash up front. "No," he insists, "he's not for sale." The ogre again increases the offer, this time to $500,000 cash. The elf finally agrees, and turns the frog over to the ogre in exchange for the money.
"Are you insane?" the bartender demanded. "That frog could have been worth millions to you, and you let him go for a mere $500,000!" "Don't worry about it." the elf answered. "The frog was really nothing special. You see, the fairy is a ventriloquist."