The recently discussed https://meshllm.cloud/ is the one I've been playing with but don't have the hardware to try with a model split between nodes, which apparently is supported and just not part of the public demo.
https://public.meshllm.cloud/ - This should give the status of their public mesh. On an average I notice around 10 nodes on their public mesh serving various SLMs. You can use meshllm to share your GPUs like SETI@Home. Wondering how security is handled at a random node.