https://www.noisetable.xyz/ - a collection of chance-based audio 'channels' in a VCR inspired interface
https://concrete95.net/ - a musique concrète web app that's made to look like windows 95. Pulls random audio from freesound.org and loops a small section, you can also layer synth pads or melodic synth loops. I'm often able to get some really pleasant background ambience.
https://windso.me - a sample-based step sequencer that doesn't let you choose the sample that's loaded, kinda fun, still needs a lot of work!