How do you feel about putting company data on a service like Dropbox which is arguably wildly insecure?

I originally used it for sharing company stuff, and then I read up on their data storage practices and moved my work stuff off there as quickly as I could. The only data I keep on Dropbox now is data I don't care really care about.

By insecure I mean that people at Dropbox are able to look at your data if they wanted to (it's against their policy, but they are physically able to). If they can look at your data then someone who hacks Dropbox can look at your data. This is placing your data at the mercy of the dropbox security team, and the ever mounting threat that the more popular they become, the bigger a target they are.

Contrast that with somewhere like SpiderOak or Tarsnap: all encryption is done on the client side, they have no idea what your data is and no one at the company can find out. This means you get to control your security (picking a secure passphrase etc).

We're using it to collaborate, generally with groups of people. As such, uber-sensitive files tend to not be the types of files we're sharing.

I like Tarsnap in theory, and as a backup solution it's great I'm sure, but it isn't meant to be a competitor to Dropbox for a lot of reasons, but mainly because Tarsnap would suck horribly at collaboration. It's far too private for that sort of thing.

For what it's worth, I've used Encrypted drives on Dropbox, and it works perfectly. It has to sync the entire volume if any one thing changes (for obvious reasons), but that solves the privacy issue. I've used it on the old 20G plan where 10G was encrypted and 10G wasn't, and it worked as expected.

The problem we constantly run into with it in work environments is that any one person is screwed if they don't have enough space for the "shared" stuff, it still all counts towards their usage.