High (in both senses of the word) population shitposting communities related to your interests are probably the best places to find these. The helldivers 2 sub back on reddit had a bunch of great ones in the early days for instance, though that sub went downhill pretty quick. But video game shitposting communities in general is where I’d recommend looking. It has to specifically be a more shitpost-oriented community though, and if you want more original, niche ones, then the community needs some sort of niche.

Lemmy probably doesn’t have the population size or overall demographics to get you particularly good results. But even here, go ask in one of our shitpost communities. And maybe dig through old threads too, since they’re usually used organically instead of dumped.

I’d share, I definitely have favorites that I’ve seen, but I don’t have a collection.