Here's a neat little story from the Midrash Rabbah.

Based on Genesis 12:14,
"And it came to pass, when Abram arrived in Egypt..."
And where was Sarah? Abram had locked her in a chest. When he arrived at the gates of Egypt, the tax officers said to him: "What are you transporting in this chest?" Said he to them: "Barley."
Said they to him: "You're carrying wheat!"
Said he to them: "So charge me the tariff for wheat."
"You're carrying peppers!"
"Take the tariff for peppers."
"You're carrying gold!"
"Take the tariff for gold."
"You're carrying silks!"
"Take the tariff for silks."
"You're carrying pearls!"
"Take the tariff for pearls."
Said they: If he didn't have something truly precious, he would not accept whatever we ask for. At that moment they said to him: "You're not moving from here until you open the chest and show us what's inside." As soon as he opened it, the entire land of Egypt glowed from Sarai's radiance.

-Midrash Rabbah