Excellent post Jon! It totally captures the vibes I got from my first few hackathons as well. The first one is always the scariest, especially when you have no idea what you are doing!
I know at my first hackathon(HackRU #2 in Spring 2012), I didn't know a single person, and I had only known about the event via word of mouth on campus at Rutgers. This was before many schools had hackathons(the only ones I knew of even a semester later were PennApps, HackNY and HackPrinceton). I had practice with my band that day for a show we were playing, so I showed up really late(around midnight), hoping my friend Reggie would show up because we agreed to work together(he bailed...classic Reggie move!). I walked in confused as hell not knowing what to do until one of the organizers, Devon, came up to me and asked me if I just got there. He brought me to the registration booth and introduced me as "a bad ass hacker who works on projects outside of school" because I told him I made a game once. This blew my mind because I had never been described as a "hacker" before, let alone a bad ass one. I had only found out the day before that the term didn't necessarily have anything to do with computer security!
At the time, I was a Physics/CS double major and the only thing I knew about programming was some Java from high school and whatever I learned in my Data Structures class. I thought that the main thing programmers were focused on was coming up with ways to make the Big O runtime of algorithms faster. So to go with the only thing I knew, I decided to come up with a data structure. I was working on a text based scrabble game in Java previously, and I knew that using an array for all of the words was very inefficient. So I came up with what I thought was a new tree structure in which the letters were stored as nodes. I pretty much stumbled upon prefix trees. I implemented this in Java with no team mate(because Reggie bailed), and coded straight through the night barely talking to anyone other than when food and t shirts were handed out. I was able to finish my hack(I built a really basic word game to demo its use) just in time to present. I was the first to demo, so I didn't know what the other projects were like. I've never seen anyone else do Big O analysis on the board at a hackathon since, but I did that day. I had some blank stares and a few laughs from the audience, but I had to leave early before all of the demos were finished(for some lame academic awards ceremony). It turns out later that I won best solo hack...because I was the ONLY solo hack! There were about 60 people at the event, which seemed like a lot at the time. I won a pretty kick ass MongoDB(although the company was called 10gen at the time) backpack, and it was all thanks to my buddy Reggie for bailing on me!
It blew my mind that there was a community like this right under my nose at school, and I knew I had to get involved immediately. Seeing the things that other people built really amazed me. I had never before thought about the fact that programmers are like wizards. You can have an idea of something that you want to exist, and in a relatively small amount of time you can MAKE that thing happen. This first hackathon experience totally changed the way I thought about everything, and I knew I needed to go to more. Unfortunately, it was the end of the semester so I had to wait until the next school year. The next spring, I went to 10 hackathons in one semester, and there were only a couple of student ones. My friends and I pretty much found anything on HackerLeague within driving distance and stormed those events. If I had decided at the time that I had too much schoolwork and not enough time to go to HackRU, then I'd be sitting in a research lab right now and I probably would not be a developer at all.