How likely was it that one plane would fly into the World Trade Center, let alone two?

I'm not going to go too deeply into speculative scenarios, but all kinds of business-interrupting calamities are possible with very low probability. We just had the story on the frontpage about the Juniper backdoor; do you think S3 isn't being targeted by multiple state intelligence agencies?

Basically I agree with https://news.ycombinator.com/item?id=10772321 - by all means keep the working copy online, but have a local offline backup.