Wow, this is a prime example of a web site not explaining what the hell the software really does.
"Sandstorm is an open source platform for personal servers."
What is it?
"Sandstorm is an open source platform for personal servers."
What is it?
So my only alternative would be to run the service myself, but then I'm storing other people's data, I have to worry about scaling if lots of people use it, and user accounts, and all this stuff.
The idea of sandstorm is folks run this platform on their personal servers, and then it lets you browse an app store like interface and one-click install these server side apps. So I'd bundle up my budgeting rails app as a sandstorm package, and if someone wants to track their expenses from a variety of devices, they install the app. Now they're running it so the data is theirs, there's no scaling issues, and user authentication is provided by sandstorm.
Sandstorm is still in its infancy so there's not a lot of apps available and the development APIs are being worked on, but I hope it's the future. It would lead to a more decentralized web with better privacy and users owning their own data.
I'm hopeful, if not optimistic, for a future where every family is expected to have their own little server running somewhere. And they access that server through the sandstorm web interface, and can easily add little apps to it. My budgeting app, a webmail app, some future federated profile app to replace facebook, etc.
With that said, it's true we've had a tough time coming up with a two-line summary that fully explains what Sandstorm is. If you could suggest what would have made more sense to you, that would be helpful. Otherwise our strategy has been to try to push people towards trying the demo, which I think illustrates what it is much more quickly than words can.