Amazon has released a new tool: Glacier. Similarly to S3, it is storage, but Glacier is a different beast. It's for keeping long term backups which you will hardly ever need, but which you need to store for one reason or another. The storage fee is just 1 US cent per gigabyte per month. The catch is, however, getting back your data. Retrieval of storage is free if you're only grabbing 5 percent of your data per month.