@palomakop I also had some success in running a synth called Phase that was designed for the pocket chip, but it's not really useful without full keyboard. maybe it's possible to remap the keys to make some use of it, but i didn't investigate it yet http://www.humbletune.com/phase/
@palomakop oh, and there's also this groovebox for pico-8. I didn't try it myself yet, but it should be fun https://luchak.itch.io/rp8