Late-night smash: Obama at G-20 summit, Rush Limbaugh

"President Obama had two meetings with Vladimir Putin," Letterman said. "Both meetings were without a shark cage."

Letterman added that insiders said the meetings went fantastic and that Putin even showed Obama his collection of stolen Super Bowl rings.

"That's Kansas City," Letterman said, looking down at his finger and pretending to be Putin. "That's a beauty, isn't it?"

Letterman then turned his focus on Syria and described the size of the rockets the country has.

"They have huge rockets full of gas, enormous payloads of gas" Letterman said. "How can I describe to you the size of these giant payloads of gas?

"Have you ever seen Rush Limbaugh?" Letterman said.