Back it up on hardware you own. You can buy multiple terabytes at low cost, you can use duplicity/Deja Dup if you want secure remote backups (on a server of your choosing), etc. You can send people files without having to rely on any specific service provider -- there is email, there is rsync, etc. It is cheap and easy to set up a file server and dynamic DNS, assuming you have a broadband connection (surprisingly many people do not, but that is a separate issue).

The problem with these web services is that they allow a single service provider to screw you over on a whim. Why put yourself in that situation? Why leave yourself vulnerable to unscrupulous competitors and governments who might try to copy your files without permission, because some service provider was more concerned about complying with warrants and monetizing your data than about security? Stay in control of your data, and you will not be posting these sorts of stories to HN.