Hi Kimberly

We have our big huge external hard drive, two laptops, and an online document library that we use for backups. Because we also run a few servers we run full backups there for websites, software applications, etc. as well.
I think the more security measures you can take the better, but I've never once backed up to a disc...those things just clutter up my space and never end up being useful in the long run (for me

)