I'm participating in the internal beta for some of the services made possible with Sun's recently announced Cloud Computing services. When I signed on I had to check a box indicating I understand that I'm not allowed to disclose any details of this beta, but since the CEO mentioned it at his blog I guess I can write something about it too.
(Aside: Jonathon writes his own blog posts. I asked. How many Fortune 500 CEOs do you know who can edit their own HTML?)
I think this is something like Sun's third or fourth attempt at computing as a utility, and I think this time they got it right. The "Save to Cloud" feature in OpenOffice and StarOffice that Jonathan mentioned is tres cool, and it's not too hard to envision things like an open source file system that stores your server files to the cloud (Oh wait, it's already there with WebDAV and DavFS!). Later this year, you'll be able to save your virtual machine to the cloud with the open source Virtual Box desktop virtualization software. Everything is built around an idea of a Virtual Datacenter (VDC) that you can use to allocate the storage and compute resources you need.
Amazon is the dominant player in the Cloud universe; if you're familiar with the Amazon Web Services (AWS) API, you'll find yourself in somewhat familiar territory with parsing XML output. What's super nifty to me, though, is the RESTful HTTP with JSON and even a drag-and-drop Web GUI interface for your Virtual Datacenter. It's very easy to get a nice little web application up and going in a short amount of time.
Amazon Web Services is very popular with web startups -- these startups use a mature, scalable and reliable web infrastructure resources offered by Amazon so they focus on developing the technology and not pay out the nose for server costs. Twitter, for example, uses AWS.
The problem Twitter now has, though, is they're tied completely to AWS. Amazon's API is proprietary to Amazon, so Twitter cannot simply move to another cloud provider or even bring their web services in house without tremendous cost and effort to rewrite, test, and debug all of their software. With an open API, such as that provided by *ahem* Sun's Cloud Services, transitioning is theoretically as easy as changing a few URIs in the software. We're even talking about marketing Cloud Services appliances to make that switch even easier. Because the API is open, there's nothing preventing IBM, Dell, or HP from doing the same thing if they want. (Oh wait: Sun's Cloud can provide AWS compatability, I'm told.)
Disclosure: I hope this is obvious, but I work at Sun Microsystems. I'm not writing on behalf of the company in this post.