Jack 'admits' that his real name is Luke Skywalker. Jack later tells Michael and Jenny that they came to Earth, "A long time ago" and Daniel adds, "From a galaxy far, far away."
After time traveling back to 1969, young Hammond says, "General Hammond Iike the sound of that". Just like Goldie Wilson says in the Future, "Mayor Goldie Wilson, I like the sound of that". Teal'c also says, "How are we going to get Back to the Future".