https://xkcd.com/1608/Go out of the play area, you have unlimited jumps. Ignore the red warning text.
If you like Yume Nikki (and xkcd), you're gonna love this. I did.
No music though.
and yes I am well aware it came out years ago. but it's still cool
P.S. there's a super long page with all the goodies about it, including some cheats if you're lost/bored
https://www.explainxkcd.com/wiki/index.php/1608:_Hoverboard