I have a number of clients whose data I archive every year. These are for apps I have written for them where they don't have a big need to do long-term historical analysis. In all of the years we have done this, nobody has ever asked to access that data.
However, yesterday, I had a call in the morning from a client who wanted to get at some #s from 2004. So in a matter of minutes, I was able to point her app to the archived data and she spit out the reports she needed.
What makes this very odd, was that at the end of the day, I received an email from a completely different client who also needed to get at some data from early 2003. A few years ago, their server crashed and burned and they didn't have backups of their own data (I have absolutely nothing to do with their systems or that data.) Luckily, I have archived my own version of the data work that I do for them and was able to get them the 2003 information.
A funny coincidence!