NCIS gets Open Source right! This is probably courtesy of Sean Murray, who is arguably geekier than the character he plays. In this episode, his character, McGee, says "I was looking for an address book, and I found Celestia, an open source astronomy program popular with space enthusiasts. It's supposed to be an accurate simulation but I found a star system which doesn't belong. The program is Open Source. That means you can adapt it to pretty much anything; education, games, you can store grocery lists, or in this case you can use it for a diary.