George Washington was naturally brown-haired (and a borderline redhead). The iconic white hair in all his portraits was not a wig, like others wore at the time, but was just his normal hair—powdered. (Source)

Washington was given a key to the Bastille after it was destroyed in the early days of the French Revolution. The storming of the Bastille was a major event at the start of the revolution, and Thomas Jefferson witnessed it as ambassador to France. But it was Washington's old friend and ally from the American Revolution, the Marquis de Lafayette, who gave him a key from the French royal prison. (Source)

The last letter Washington ever wrote was to Alexander Hamilton. A couple days before Washington died, he sent Hamilton a letter praising his idea for a national military academy. (Source)

Aaron Burr once helped prevent a duel between Alexander Hamilton and future president James Monroe. Burr, the man who would later kill Hamilton, was also an old friend of Monroe's, and when Monroe and Hamilton were preparing to duel in 1797 over an argument and the publishing of some very private papers, Burr was asked to step in. (Source)

George Washington had to deal with pirates during his presidency. Legitimate, old-school pirates. In 1785, a ship with 23 men was captured by Barbary pirates from Algiers. Between the changing government and problems getting funds, the men weren't ransomed until 1795, when Washington finally secured enough money from Congress to get back the 10 men who were still alive. (Source)

The "whiskey tax" suggested by Hamilton (which caused the Whiskey Rebellion of 1794) affected Washington himself. He ran a distillery on his estate at Mount Vernon, which at one point was actually the largest whiskey distillery in the country. And yes, he paid the taxes. (Source)