Despite all the usual warnings associated with installing beta software on production machines, staying on the bleeding edge sometimes does have its advantages. Here's a little story to illustrate this point...

Some of you might know that I run the Folding@Home distributed computing client on my main desktop. This machine has been running the monthly Vista builds for a while now. The other day, I accidentally hit the switch on the power strip, and the machine turned off. Since the Folding client was in the middle of writing to the disk when this happened, the checkpoint data file was half-written, and the client had to restart the computation from scratch when the system restarted.

So I went into the Folding@Home directory, and clicked the "Previous Versions" button on the Explorer toolbar. I was presented with a list containing versions of the files as they existed the in the past. I selected the version from the day before, allowed Vista to do its thing, and restarted the Folding client. Now that the checkpoint files were intact, it was simply able to resume from where it had left off the previous day.

Okay, so the Folding data was not really all that critical. But had I accidentally deleted or lost something more important, "Previous Versions" would be the first safety net that I could have fallen back on. And it's always nice to have a safety net... :)