Minecraft before Microsoft bought it out and forced me to make a Microsoft account just to play it.
At some point, I had stopped playing Minecraft and I had an account since alpha but because of their account migrations where I hadn’t created a new username on the 2nd sign on system and the fact that so no longer had a receipt, I wasn’t able to recover my account. It was quite disappointing.
But I bought an account to play on Windows in bedrock because my son started playing and he wanted to play together with me. We still play and we could play for hours, just exploring and mining for stuff.
Building a cloud castle out of colored wool blocks in survival with my then girlfriend (now wife).
Hanging out with friends in the /r/Minecraft irc channel. Talking with etho was cool too, albeit brief. Also, playing on oc.tc back in the day with them, which is what inspired Minecraft to implement the ding sound when you make a hit with the bow.
Edit:
Oh yeah, Minecon in Florida was cool too. Sethbling and I rode the teacups together at Universal.
Playing just as it left alpha and exploring, listening to my music.
Playing in a world created by my boyfriend and his sons. We made a huge mine. I remember a cobblestone tower. Just in front of this was a small pool of water where I once died because of the bug that didn’t allow you to swim up while taking damage. We started with a small wood house and eventually made a castle out of smooth stone. It had a library and a kitchen and 4 beds - One for each player. I didn’t have an Xbox live account so when we played I was always logged in as a guest. Before leaving the game I’d remove all my armor and empty my inventory into a chest for the next time I joined.