John Laurens was a state legislator from South Carolina who, like Hamilton, was an aide-de-camp to General Washington in the war. His father, Henry Laurens, was the President of the Continental Congress. Hamilton wrote a series of what are sometimes referred to as "love letters" to Laurens. Whether their relationship was ever sexual is not known, but history books often ignore this portion of the statesman's written legacy.
John Laurens was killed in battle late in the war. Hamilton and Laurens are depicted together on the "Surrender of Cornwallis" commemorative U.S. postage stamp released in October of 1981.
OMG. This was the best part of my research. XD (Alexander Hamilton! Why do you have such slash appeal?)
(ETA: this is from this Alexander Hamilton page, which, I must admit, has a bias. Which doesn't invalidate it, of course; only means that it should be taken with a grain of salt. Le sigh.)