i have found by now :

For modded Minecraft https://forum.feed-the-beast.com/

For the Hitman games https://www.hitmanforum.com/

For knitting and crochetting https://www.ravelry.com/

For cannabis-related https://future4200.com

For cactus growing https://cactiguide.com/cactitalk/

Competitive mario kart https://mariokartboards.com/

Rpg.net is a nice place to discuss ttrpgs

An ancient 2chan clone for discussing trains https://www.1chan.net/

shroomery.org for mushroom cultivation and general discussion

forum.paradoxplaza.com/forum for Paradox games

https://cs.rin.ru/forum/ good source for updated pirated games and DLC (some chuds on here, but it’s mostly centered on games)

https://forums.mydigitallife.net/ for pirated software (usually mainstream and niche Windows versions, MS Office, some Adobe). It could be very technical at times, so you’ll have to do some research before downloading and installing anything.

Nedesigns.com is a Rollercoaster Tycoon fan site

https://www.geeksforgeeks.org/ for coding

(i will update this with the comments)

  • sailorfish [she/her]
    ·
    4 years ago

    It's not actually niche (it has like a million active monthly users) but https://www.ravelry.com/ for knitting, crocheting, and other fiber arts. If you ever considered getting into one of those and don't know where to start, they have links to a gazillion free patterns and a very robust searching system. The people on the forums also seem nice, though I haven't interacted much.

  • charles_xcx [he/him]
    ·
    4 years ago

    I just found this succulent & cactus growing forum today:

    https://cactiguide.com/cactitalk/

    a couple of my cacti flowered over the summer and I ended up with seeds, so I've been looking through it for resources on germinating them

    • WorkerOfTheWorld [none/use name]
      ·
      4 years ago

      Love that forum!

      I'm jealous of your flowers, cacti flowers are so beautiful!

      I need to figure out what to do with my trichs for the winter..

      • charles_xcx [he/him]
        ·
        4 years ago

        I love the way the flowers smell lol. but i'm jealous of your trichs! mine are just ornamental plants but I really want to grow some active ones

        • WorkerOfTheWorld [none/use name]
          ·
          4 years ago

          They do smell amazing. Any particularly cool ones you grow?

          Do it! Active ones are even more rewarding to grow 😁

          • charles_xcx [he/him]
            ·
            4 years ago

            not really, I just bought a bunch that looked cool a few years ago lol. I have an echinopsis that flowers every year, a gymnocalycium that I got seeds from this year, a rainbow hedgehog cactus, and another mystery barrel cactus I'm taking care of for a friend that also gave me seeds. plus a couple aloe and an elephant bush that I almost killed but is now thriving lol.

            can you recommend any vendors? I've heard that you can sometimes find trichs at lowe's but they're not always active.

  • WorkerOfTheWorld [none/use name]
    ·
    4 years ago

    https://future4200.com for everything cannabis-related. A bunch of asshats on there, but they tend to share useful methodology and a wealth of knowledge.

  • CarlsJrMarx [love/loves, des/pair]
    ·
    4 years ago

    Nedesigns.com is a Rollercoaster Tycoon fan site where people upload extremely intricate, and often times ultra realistic, parks made using custom scenery objects and programs that allow one to hack the game

  • Potap [she/her]
    ·
    4 years ago

    Rpg.net is a nice place to discuss ttrpgs. Haven't visited it in a while though.