I bought the Jungledisk client, but have not used it yet.

do you use S3 or any other online backup service with any of your clients at work?

No. Our FAIL. But I don't make the rules.

So what sort of backup do you traditionally use? Any off site at all?

We tell someone onsite to take a tape home every night.

We used tapes, but with the low cost of HDDs I moved to them. I switch them off weekly and take the one home.