Today Amazon Web Services (aws) introduced a new archiving solution: Glacier. It's for archiving data and has a very, very low cost of only one cent per gigabyte per month. Amazon says it's for archiving and backup data. On the surface, it looks good: very few limits, handles huge data, good API, very low cost. But I'd never use it for backup. Why? The restore time. Amazon says once you request retrieval, it may take 3.5 to 4.5 hours to get your data staged to be ready for retrieval. A wise SysAdmin friend of mine once said "The most critical part of backup is recovery time. After that, almost nothing else matters in terms of speed." He's right. When a system's down and dead, the amount of time it takes to recover data from a backup is the main thing, the ONLY thing. I just can't see waiting 4 hours after a crash to get you data ready to be downloaded as a viable backup strategy for any online business.