Microsoft Office 2013
According to a recent article appearing on geek.com, retail editions of Microsoft's Office 2013 are linked to a single computer for life. What this means is that if your computer fails or you buy a new one, you cannot move your copy of Office 2013 over to the new machine. You will need to buy a new copy of Office 2013 to run on the new machine.
Earlier versions of Microsoft Office worked differently. You used to have a single device license, which meant that when you bought a copy of MS Office, you could run it on one machine and then move it to a different machine in the event of a machine failure.