Boris Yeltsin

Boris Yeltsin shares a laugh with American President Bill Clinton outside the White House in October, 1995.  The two men got the giggles during a press conference after Yeltsin had a funny exchange with a reporter. Video of the moment remains popular online.

Photo from ITAR-TASS via the office of the Russian president (kremlin.ru). Reprinted via Wikimedia Commons, under a Creative Commons 3.0 license.