The NPC 'Jakben, Earl of Imbel' found in the Imperial City is actually an anagram of "Jack be nimble", from an old mid-19th century English nursery rhyme about a boy named Jack who would jump over candle sticks. He also owns a pair of unique boots important to the Thieves Guild questline which boosts the wearer's acrobatics skill by 50 points, allowing them to jump much higher than before. The name of the item, the "Boots of Springheel Jak", is itself a reference to a character from English folklore.
Contributed by G-Haven