At work we use NetApp. It does hourly incremental and nightly full backups. The backups are replicated across 2 datacenters. It's pretty expensive, but it's

At work we use NetApp. It does hourly incremental and nightly full backups. The backups are replicated across 2 datacenters. It's pretty expensive, but it's the only sane way of managing backups for 200+ sites across too many servers to count.