Redundancy vs. backups

Usually, backups give you data redundancy. In this article I want to consider functionnal redundancy.

Of course you have to backup often. But what if one of your backups could be used directly if the original machine breaks ?

I usually backup all my code to an old laptop. In case of emergency I can switch workstation rapidly. It does not really affect geographical repartition of your backups but at least you always have one that is directly usable.