I don't have recent numbers in front of me, but I believe our web servers are more like 40% of our hosting costs today. Over the past year, we've started lever

I don't have recent numbers in front of me, but I believe our web servers are more like 40% of our hosting costs today. Over the past year, we've started leveraging our CDN (Fastly, who have been great) a lot more. That said, for us a lot of logged out traffic still carries the weight of logged in traffic. A logged out user can start doing math exercises and we'll keep track of what they've done. If they then create an account or log in, that activity is associated with their account. Khan Academy may look like a content site, but in many ways it's more like a "learning app".