Lightcrest is a complex managed hosting provider that works with clients to ensure HIPAA compliance. We build fully managed environments (servers, storage, network, physical security) and work with application developers and management on a variety of compliance issues.
You forgot to mention bandwidth as part of the fundamental datacenter cost structure. Some datacenter operators are charging up to $200/month to drop dark fiber into your cage/rack/cabinet. It is then up to you to negotiate a primary and secondary connectivity provider. At non-bulk rates (meaning around 10-100Mbps) this can be up to $50/megabit. Bulk rates look better - but only because if you're pushing that much traffic, you must be rich.
This is part of the reason cloud computing should be taken with a grain of salt. There can be fantastic economies of scale when applied correctly (say, on a properly built CDN solution) - but be wary whenever "cheap" and "computing" are mentioned in the same sentence. Someone has to be paying for all of that power, space, and bandwidth.
http://www.lightcrest.com