I don’t know of any super high-quality ones that run well, but the Open Assistant project, (now archived) collected responses from voluntary participants (myself included) to build what is now considered a very high-quality dataset of chat conversation pairs, truly open source, and all voluntarily submitted instead of scraped.
The models are reasonable for fine-tuning, but aren’t very good compared to newer models from large companies.
To counteract the somewhat clickbait-y title:
There’s still no indication it’s spreading between humans, and it doesn’t seem to be “raising anxiety,” at least not in any significant way. “This will be of enormous interest” - DR. William Schaffner, an infectious disease expert