Very interesting statistics from Tokki. Even when keeping the original files, a resize image, and a thumbnail image, we get an average filesize of 160K per image (I'm going to boost this number to 185K because there are some extra files stored for each image).

I originally thought it would be more along the lines of 300K conservatively ... this has a deep impact on what I consider the commercial viability of an online gallery site.

Let's assume for a minute that you launch a online gallery site. You offer 1200 images for a paid account. For the moment, let's simply assume that we are worried about the costs of such a service. Let us also assume that bandwidth is not an issue, but hard drive space is the main constraint of such a site.

With 1200 images, the total hard drive space is roughly 222 megs. Conservatively, we can assume a typical image gallery storage site will be working roughly 80 gigs of HD space (the real space would be 160GB, but we're RAIDing the two hard drives for backups sake). That means we can run roughly 350 paid people per server. Therefore each user must pay roughly $0.40 to pay for a server. With taxes and unexpected charges ("the costs of running a business"), we can expect a charge of roughly $0.75 per user to pay for a server.

Of course, such a site would have tons of free users, so that cost goes up a lot.

But this is very interesting. I thought the economics on such a site were a lot worse.