What Is Inside Should Be Outside

I'm a gamer and a geek. I stay up-to-date on technology news. I play plenty of video games. Yet my wardrobe doesn't reflect this. I wear business casual clothes to work (and I wore casual business clothes to my last job). I have a few geek T-shirts, but I almost never get a chance to wear them. 

Now I never really thought this was a problem until after a meeting with the reverend presiding over my wedding. He told us that we should try to get elements of things that are important incorporated into the wedding. He gave the example of a poker-playing groom who carried a royal flush in his jacket pocket. Even though no one saw it, it was a part of his special day. I said, "Hey, I could bring a little Master Chief chotchke in my jacket pocket," and chuckled. But then I got to thinking and realized that I should make my geekiness a part of every day.

My first thought was a geek-themed necklace; I was encouraged by this item blogged by Hawty McBloggy (yes that's the actual title): 

While this is awesome, it's a little too  flamboyant for my tastes (plus I never play the guitar in Rock Band, only drums or singing). Then I remembered this little item from SplitReason:

I could manage this, though the dog tag style isn't really me. I want something simple that fits beneath my clothes (making a necklace ideal). I really want to do something like this but I also don't want to look like a total tool. Any thoughts?