This is something really simple, yet a lovely demonstration of a concept. The idea is that members of a journal club meet regularly to discuss a journal article. The site appears to have been designed for in-person meetings, though it would be effective (maybe even more so) online. It's connected to the arXiv library of papers so it's easy to recommend and select a paper for discussion. A presenter can then add slides and set up the meeting. That's it. This is a very small and seldom-used site, and I can't imagine it will become the next MeetUp or anything like that. But it really illustrates how you can create simple tools to enable self-supported learning in groups quickly and easily. I created an Ethics club and set up the first presentation in less than 5 minutes. I don't intend to actually hold it... but hey, if a bunch of members join, maybe I'll change my mind.