or, i attach a gameboy rom to a post, and there's a big play button on other people's timelines
honestly though, i do miss the flexibility of email attachments. right now if i want to link even a tiny file, i either have to smuggle it inside a blessed image format, or i paste some base64 code under a read more, and hope people are unix enough to care to decode it
it is way easier: you can use data: urls with b64! select the text below (triple-click it) and drag it into your current tab like this:

and yes, this requires 0 external code. this is an attachment! you can do up to 200kb in here lol

← {⊃1 ⍵ ∨.∧ 3 4 = +/ +⌿ ¯1 0 1 ∘.⊖ ¯1 0 1 ⌽¨ ⊂⍵}