No specific memory to speak of, just a mashup of several LAN party moments.
When I think about Halo, I'm always taken back to my high school days when Halo CE was brand new. Halo CE was released at the start of my freshman year of high school and we would frequently meet up at my friend Alex's house for LAN parties. This meant dragging along my 27" CRT tv since this was before the days of flat-screens. And then, there was always the mad scramble to find long enough ethernet cables to connect to the router.
Once things were situated, we would engage in hour+ long CTF matches. Our house rules prohibited things like blocking the teleporters on Blood Gulch or throwing the flag through the bars on Sidewinder. Getting caught doing these things by the other team was a mortal sin(but of course people occasionally tried). After each match, our system for balancing the teams was for the losing team to declare a player trade. With the way Halo profiles were created and managed on the original Xbox, it was easy for players to jump back and forth between different consoles as there were no gamertags to manage or worry about.
Our food of choice was always Dominos Pizza. We ordered pepperoni pizza and buffalo chicken Kickers. For those who don't remember what Dominos chicken Kickers were, they were basically just boneless wings with a fancy name. They were delicious though.
We never stopped having Halo CE LAN parties, but the form has changed. Now, when we get together, we all drag our Xbox Ones with us and use MCC to play our CTF matches. There are extra hurdles to jump now with the Xbox Live dependency and the gamertag management. Dominos no longer sells chicken Kickers where I live, but we can still order pizza and boneless wings. But despite the changes we've had to endure, it's worth it to keep the battle for those damned flags raging.