Hacker News Reader

IO has been around for a while now, I remember it got some press back when _why was still active:

I've played around with it a bit over the years: it is a fun little language.

Edit: fixed typo.

I'm fond of the post Lazy Bricks, Lazy Mortar¹ where he basically pulls a rabbit out of a hat. It's a shame he didn't write more posts about Io.