I love Colbert, but I don't see what was particularly funny about that specific joke.
Wikipedia entry on plot...
"In order to make himself appear more important, a miller lied to a king, telling him that his daughter could spin straw into gold. The king called for the girl, shut her in a tower room with straw and a spinning wheel, and demanded that she spin the straw into gold by morning, for three nights, or be executed (other versions have the king threatening to lock her up in a dungeon forever). She had given up all hope, when an impish creature appeared in the room and spun straw into gold for her in return for her necklace, then again the following night for her ring. On the third night, when she had nothing with which to reward him, the strange creature spun straw into gold for a promise that the girl's first-born child would become his.
The king was so impressed that he married the miller's daughter, but when their first child was born, the imp returned to claim his payment: "Now give me what you promised". The queen was frightened and offered him all the wealth she had if she could keep the child. The imp refused but finally agreed to give up his claim to the child if the queen could guess his name in three days. At first she failed, but before the final night, her messenger discovered the imp's remote mountain cottage and, unseen, overheard the imp hopping about his fire and singing. While there are many variations in this song, the 1886 translation by Lucy Crane reads:
Today do I bake, to-morrow I brew,The day after that the queen's child comes in;And oh! I am glad that nobody knewThat the name I am called is Rumpelstiltskin!"[SUP][1]"
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So it was clever in that it called them out on not "knowing his name". And that if they did he would teach them how to spin fiat "hay" into real "gold"..i.e..if he became President there would be a gold standard of sound money but they have to speak his name...The first born child is the nomination and subsequent Presidency, so within the joke is subtle sarcasm, a strike at the panelists, an evocative image of RP as an imp who can turn hay into gold as well as their narrative into pwnage and is a major cognitive loaded truth bomb. The laughs were the results of that cognitive dissonance taking many new tangents in their constructs and they couldn't contain the neurological overload. Great stuff.
Rev9