Did you look into online backup? If your data is important and you are worried about concerns of fire/flood in addition to computer crashes and hard drive failure this may be an option for you.
Pricing often starts at under $5 a month for unlimited storage per computer, and you can find discount codes and specials online to give you a month or two free.
The downsides to this method are:
1) Cost – what you would end up paying for 2 months of online backup for a single computer, could buy you an external hard drive that you can use for more than just a single unit.
2) Time – In case disaster strikes and you lose all of your data, the speed of your internet connection could limit the transfer speed of data back on the drive. With a Hard Drive, you could just copy and paste right back on. (You should also note that the initial backup will also take a while, so its recommended you run it overnight)
Personally for important files I use my one of my web hosting plans for storage. I know that I will have access to them wherever I need, and my hosting provider backs up their servers in case they go down…so its a double layer of security for me.