We've done a lot of work on locking stuff down, and the back-end runs across a number of servers, so it would be pretty hard to take down the site as a whole.

We've done a lot of work on locking stuff down, and the back-end runs across a number of servers, so it would be pretty hard to take down the site as a whole. But yeah, there are bound to be loopholes. OTOH, if we're charging for compute time and someone chooses to write something that locks up the server completely, then, hey, it's their money ;-) So long as we can keep it running for everyone else, anyway. We're a bit more worried about how to stop people from using it to create a botnet or otherwise use it to do Bad Things to other people; but I guess every cloud computing service ultimately hits that problem, and all you can do is monitor and shut stuff down quickly if something bad starts happening.