Honestly, a lot of NSFW subs devoted to somewhat niche fetishes. I saw lemmynsfw.com started up as a separate instance for NSFW content, and I'm hoping at least some of these subs make it over there soon.

Not ashamed to say trashyboners. Someone's gotta stand up for the trash of this world.

r/cancer It was a nice space to find support of other people going through what I'm going through.

my first comment!

i’m going to miss formuladank. i’ll try to start every single sub i’ll miss on here though. my account is only a few minutes old

I'm gonna miss /r/buttcoin. It's a great place to watch crypto bros lose everything. How will I know when cz is arrested?

Game specific ones. /r/hyruleengineering and /r/darktide as recent ones.

All the /r/_irl communities. The later seems like one I could probably just start and post in, even if no one else sees them.

All the cat subs. If I was having a shitty day I could always go to reddit and look at other people's cats.

r/Fedora and r/ThinkPad. Those are the two I spent the most time in. I will also really miss my guilty pleasure subreddits like r/gaystoriesgonwild, r/Twinks, and r/GayKink. Haha.

The gardening subs always made me feel like I could do anything in my tiny garden as long as I put in the work.

If I’m being honest, I was a big browser of NSFW subreddits and I’m hoping that lemmy will grow and create a space for NSFW communities that are well-moderated and safe.

r/Buttcoin

All the mycology subs, but I'm thinking of rebooting them here. All the synthesizer subs. All the subs with eerie places like r/AbandonedPorn, r/RustyRails etc.

I'm going to miss browsing r/all for a good laugh and interesting stuff. I'm going to miss stumbling upon random subreddits with topics and interests I didn't even know existed like r/Jarrarium, r/DesirePath or r/ThatBathroomMazeDream

I'm going to miss all the curly hair subs, it's a niche topic but something I feel like I know a lot about. I really wanted a text based of the main sub though, apparently I found r/curlyhaircare is like that. Going to not go on reddit though as much as possible.

I'll miss clicking Top of All Time in all subreddits. In here I have to wait YEARS before I can find the Top of All Time content.

I’ll miss all my goofy cat subreddits. They were kind of my go to when I was having a crap mental health day.

bestofredditorupdates, watercolor, embroidery, fitness, fundiesnarkuncensored, cooking.. there’s a lot. This is so sad and I hope Lemmy really takes off. And if it does I hope some of these talented developers make bad ass apps for it

There are so many… I used the platform for 8 years and really learned something new whenever I opened the App… I hope a lot of them will find their way over here.

All the porn and nsfw content. Brings a tear to my eye.

/r/OnlyFans
https://web.archive.org/web/20230325223700/https://old.reddit.com/r/OnlyFans/

Since i'm just starting to get into home lab and self hosting I'll miss r/homelab, and r/homelabsales

It’s just cool to see the variety of refugees here sharing memories of their previous communities in the once glorious homeland made uninhabitable by the authoritarian regime.

So many...

Wallstreetbets, NonCredibleDefense, all the comedy and podcast subs dunking on Joe Rogan. Last couple years though I got heavy into NFL Meme War subs. Those had some top tier content during the NFL season.

Nosleep and its assorted subs... I've been reading there since it had roughly 300 subscribers. I really hope the community rebuilds here.

HobbyDrama and similar subs. They're the Fandom_Wank of the Reddit era and I honestly love every bit of it. I'll miss Rimworld, too.

I might be older than a fair amount of you on the fediverse, but I'm going to miss Daddit. It was a super supportive community. I'm also going to miss nosleep, I really enjoyed a lot of those multi part stories! Other than that, I think I'm just going to miss all the random stupid posts I saved over the years and went back to here and there for a good laugh.

i’m definitely going to miss r/BuyItForLife. it was really nice to lurk on there and find good quality products like darn tough socks being recommended to people. found my backpack there too and it’s the best i’ve ever had.

I loved r/hobbydrama, it was such a good place. :<

Maybe BestofRedditorUpdates, sometimes I really enjoy getting into a nice long story, even if some of them are probably fake. Also some of my country specific subreddits.

Several of he hobby ones. Ben Eater (6502 based computers, 8 bit computer), local ones, history/science based ones, infosec/sysadmin/etc. ones. There are some Lemmy based ones, but it'll take a while to build up. I'm hoping that I can contribute to them and see them grow a bit. But, others are just where I could comment and enjoy as I lack the real knowledge to contribute very much (the history/science ones that required more in-depth knowledge and not just a "Wikipedia degree of arts of internet research for obscure questions".

/r/history heavily moderated and has actual historical experts answering questions and has a big library of already answered questions.

The medical subreddits. So, SO much information for people. When I was newly diagnosed with something, it was very helpful to go to the sub and see how others’ lives were, tips on management, and med side effects.

All of them. There’s so much collective knowledge stored in the comments, posts and subreddit menus, and it’s going to disappear. Stupid spez

I'm really going to miss anime_titties; for anyone that doesn't know, it was a wildly inappropriately named serious subreddit focused on interesting, relevant, unbiased world news that actually affected people.

r/StupidFood, I need my daily dose of stupid and disgusting food videos :(

r/WhatIsThisThing, r/TipOfMyTongue, and similar subreddits. Some of the simplest and best examples of the power of crowdsourced knowledge. Take a simple question with a simple answer that is basically impossible to search through conventional means, but through the power of those communities you can get your answer in minutes. Simply amazing.

Lemmy is going to have to get huge before it can really replace them. :/