As a part of Fans For Christ I organize and lead church services at cons, usually giving the message. The first time I did it I had a sermon that included some Star Wars references, but was that was not really my main focus. In fact, I only used it because I had given the sermon in a traditional church once and had it handy. However, I realized the benefit of people being able to relate to the message illustrations.
Jesus and His Apostles (sounds like a boy-band, doesn't it?...no disrespect meant, Lord) used illustrations and analogies that their audiences could understand. Look at the parables and stories in the Bible and you'll see that they mostly include references to farming, winemaking, soldiers, and athletics...all things that the people of that day and age understood and could relate to. That's really my inspiration for my sermons. I want to talk about the Bible in ways that makes sense to my audience, yet still is teaching God's Word.
Preachers do this all of the time in modern churches. And what is one of the biggest topics for illustrations? Sports. Football, basketball, baseball, hunting, fishing, and so on. Personally I could care less about any of these things and my friends are often of a similar mindset. When I go to places like Dragon*Con and ConNooga, the interests of the audience are even more shifted to Star Trek and Harry Potter and away from the Dallas Cowboys or deer season. So why shouldn't I use those things in my sermons?
Want to see what this is like? Fans For Christ now has a YouTube channel. Some of the videos we've linked and are uploading are taken from services. Others are me recreating messages that I've given in the past but didn't have recorded. Take a look and see some geek preachin'!