Today's historywebsite concerns William Parker and the Christiana Resistance, also known as the Christiana Riot. The story is briefly that a group of Blacks ed by William Parker resisted an attempt by a slave-holder to redeem his fugitive slaves by shooting him. You will probably find more about the story in this book, Bound for Canaan, a recent popular history of the Underground Railroad.
What I find most notable about this story is that the defendants were found "not-guilty," perhaps because of the venue of the trial and perhaps because the defense attorney was none other than Thaddeus Stevens. It's also interesting that, as Edward Steers, Lincoln assasination expert has noted, that John Wilkes Booth was influenced by the story of these events.