Azure Table storage is very efficient NoSQL store offered as an Azure Service. Many times you would want to retrieve the latest n number of entries from your data store. In order for this operation to be efficient, your entries should be stored in reverse chronological order. In Azure Table storage land this means creating an appropriate RowKey for your data entries.
If you are new to Table storage, you could check out this fabulous article on the internals of this service and how it operates.
The important piece here is the GenerateKey() method. It returns a RowKey in the format of "reverse-time:guid" which will automatically make the newest entry to be sorted at the top. Once you have this in place, you could easily query your table store for the latest items.