Just read a nice blog post by @4nd3rs (in Danish) about his considerations about online backups; what to use and local vs. remote backup.
In the following I will try to describe my own setup. It has been a work in progress, but right now I feel it meets the requirements of myself and the family.
As any other modern family we have a number of computers running both Windows and OSX. When we moved into our house, I decided I did not want to run any cables anywhere or rather my wife decided we did not want to do this, so all devices are connected using wireless to the internet and the NAS.
The main storage and backup devices is a Drobo FS with 3 TB of storage. Data Robotics has their own concept of RAID, called BeyondRaid, and having three disks in the NAS enables it to exercise protection for single disk failure. The Mac is using the Drobo for backup via TimeMachine. Apart from shared documents the main content of the Drobo is pictures and music as the device also serves as storage for our Sonos music system. Whatever requirements the Windows machines have for backup, it is handled remotely.
For remote backup we recently moved from using JungleDisk and Amazon S3 to iDrive. For iDrive I have a Pro-account where the Drobo is back up to and each other family member has their own Basic account. The professional account is $5/month for one PC and 150GB. They have a family pack for 5 PCs and 500GB, which is $15/month; I guess we will move here when the need raises.
The main reason from moving away from Amazon was cost. It is dead cheap if you only have a small amount of data, but can get quite expensive if you have a lot, especially to extract the data if required.
We also use DropBox and each of us has an account. Personally I can’t remember when I used an USB stick last. It is just great for “moving” files back and forth, e.g. between work and home, and also for file sharing.