Tempest is a survival game built in pico-8. It’s challenging, but it’s also a lot of fun.
Apparently today is Andrew Talks about Pico-8 day. (See Tempest, Combo Pool) Following that same line of thought, here is an Excellent demake of StarFox for the Pico 8. It’s in 3D, it’s got a rockin’ soundtrack, and it’s an absolute technical marvel.