Wow. The course the OER Foundation is currently facilitating for 1200ish educators concentrated in the South Pacific, is running on a USD50/month Digital Ocean droplet. The initiation of the course, when you'd expect max resource hit is showing ~ 10% *peak* (CPU & Memory) resource use on that system. That suggests our infrastructure could easily handle 10x more learners or 10k learners. So that suggests a per learner cost of USD0.005/month. I'd say that's pretty cost-effective.