I want to have a really different wedding, what should I do?

My husband and I are already married (he’s a Marine and we just wanted to be together and have a big wedding later). We’re both gamers, we both enjoy rock music, and are a couple of geeks in general. We want to have a fun wedding, and I’d like to either put a spin on the traditional stuff (example below) or cut it out all together.

We’ll have both a ceremony and a reception in the same place (it looks kind of rustic… stone walls, beautiful wood floors and ceilings). We’re trying to have a good compromise between something we enjoy and something affordable. Like using my laptop instead of a DJ or something.

Let me know what you all think! I’m up for any suggestion no matter how weird/expensive/whatever it sounds. Anything to help me think outside the box.

Here’s what we have suggested so far:
– (example from above) I’m going to have my great aunt make a false cake, and have it look exactly like the cake from Portal. (The cake is a lie, remember?) That will be on the top tier, and everything below it will be cupcakes. We’re still deciding if we just want pretty, regular ones or if we’ll have white icing and use a black frosting/writing/gel/whatever thing to make the images from the game. Either way, I will be helping to make them. Fun on a budget!
– I was thinking of using Final Fantasy music during the ceremony (victory theme after the kiss!)
– Would it be okay to ask guests to just bring food? We’ve been married for 8 months, and pretty much have everything in the house we need. As much as we love presents, it would be a greater gift to not have to pay for a caterer.
– He suggested zombies. But I don’t really know where to go with that other than making our wedding parties dress up like them (bwahaha). We’ll only have two or three people each.
– I’m thinking that if I want to go the extra mile, I could put little party favors in a Weighted Companion Cube I can make from cardstock. What to put in it though?
– I suggested this in an email: “Dude, what if we stood on the stage and had an image projected at the bottom, and at the “I do” part have our ATB timer fill up (FF7 battle system), and give us the “I Do” option, that is selected for each of us. At the end, we could be put in the same party, and have our limit breaks! :D”

I know this is soooo long, but I mean, its me. I can’t be concise to save my life, and this is also brainstorming.